2.) What value for c will make the expression a perfect square trinomial? x2 – 7x + c -49/4 -7/2 7/2 49/4

QUESTION POSTED AT 18/01/2020 - 07:30 AM

Answered by admin AT 18/01/2020 - 07:30 AM

Answer :  \frac{49}{4}

Given expression is   x^2 - 7x + c

To make perfect square trinominal we use completing the square method

In completing the square method we add and subtract the half of square of coefficient of middle term

Here coefficient of middle term is -7

Half of -7 is  \frac{-7}{2}

Square of  \frac{-7}{2}  is  (\frac{-7}{2})^2  =  \frac{49}{4}

So the expression becomes   x^2 - 7x +  [tex] \frac{49}{4}  that gives perfect square trinomial

Hence , the value of 'c' is  \frac{49}{4}


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Related questions

If f(x)=(3x=7)^2, then f(1)=?

F(x + 1) = 3(x + 1) + 4 = 3x + 7
Hopefully this helps

ANSWERED AT 24/02/2020 - 12:36 AM


QUESTION POSTED AT 24/02/2020 - 12:36 AM

(1 pt) Uncle Mark's family drinks 12 quarts of milk every week. Which expression could be used to figure out how many gallons of milk they drink every week? (4 quarts = 1 gallon) A. 12 – 4 B. 12 + 4 C. 12 × 4 D. 12 ÷ 4

So Mark's family drinks 12 quarts of milk every week. And it asks us, "Which expression could be used to figure out how many gallons of milk they drink every week?" And it also tells us 4 quarts is 1 gallon. If you want to convert quarts to gallons, divide quarts by 4.

So, the answer is D. 12 / 4


ANSWERED AT 24/02/2020 - 12:34 AM


QUESTION POSTED AT 24/02/2020 - 12:34 AM

An electrician charges a flat fee plus an hourly rate for a service call. She charges a total of $94 for a 3-hour service call on Monday and $130 for a 5-hour service call on Tuesday. How much should she charge for a 2-hour service call? $36 $52 $76 $98

Answer: Third option is correct.

Step-by-step explanation:

Since we have given that

Charges for a 3 hour service call on Monday = $94

Charges for a 5 hour service call on Tuesday = $130

So, our coordinates will be (3,94) and (5,130)

As we know the "Two point form":

y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)\\\\y-94=\frac{130-94}{5-3}(x-3)\\\\y-94=\frac{36}{2}(x-3)\\\\y-94=18(x-3)\\\\y-94=18x-54\\\\y-18x=-54+94\\\\y-18x=40

Now, we need the charges for 2 hour service call.

Let x = 2 hours

We get that

y-18x=40\\\\y-18\times 2=40\\\\y-36=40\\\\y=40+36\\\\y=76

Charges for 2 hour service = $76.

Hence, Third option is correct.

ANSWERED AT 24/02/2020 - 12:34 AM


QUESTION POSTED AT 24/02/2020 - 12:34 AM

Reg has just purchased a new car. The car had a list price of $22,499, and he was responsible for 7.96% sales tax, a $2,138 vehicle registration fee, and a $262 documentation fee. Reg’s financing has an interest rate of 10.27%, compounded monthly, and a duration of three years. If Reg makes a monthly payment of $773.89, which of the following was his down payment? Round all dollar values to the nearest cent. a. $2,000 b. $2,200 c. $2,500 d. $2,800

Answer:

The answer is option D: $2800

Step-by-step explanation:

As given, there was 7.96% sales tax, $2,138 vehicle registration fee, and a $262 documentation fee.

So, total Amount becomes = 7.96 \% \times 22499 +262+2138+2249

= $26689.92

Reg’s financing has an interest rate of 10.27%, compounded monthly, and a duration of three years.

r = 10.27% or

n = 12\times3 =36

Also given that Reg makes a monthly payment of $773.89.

Monthly payment = 773.89=\frac{(22499-x)\times \frac{10.27}{1200}}{1-(1+\frac{10.27}{1200})^{-36}}

Solving this we get;

x = 23889.84

Hence, the down payment was = 26689.92-23889.84=2800.08 dollars

Therefore, the answer is option D: $2800

ANSWERED AT 24/02/2020 - 12:33 AM


QUESTION POSTED AT 24/02/2020 - 12:33 AM

A slice is made parallel to the base of a square pyramid. What is the shape of the resulting two-dimensional cross-section?

Answer:

You get a square, I just took the test and got it right.

Step-by-step explanation:

with a square pyramid the base would be square so by cutting parallel of the shape you basically are left with the shape of the base.

ANSWERED AT 24/02/2020 - 12:33 AM


QUESTION POSTED AT 24/02/2020 - 12:33 AM

If m <2 =40o then What does m <z equal

For the small triangle, <2=40, so we can add 40 to the 90 degree angles to get 130. subtract 180-130 to get the remaining angle in the small triangle to get 50.
The remaining angle, 50 is also the angle to the large triangle. So Since the top angle of the large triangle is =90. So add the 50 and 90 to get 140.Subt 180-140 because the total of the large angles should be 180 degrees. That leaves 40 degrees for angle z. So that would be B.

ANSWERED AT 24/02/2020 - 12:33 AM


QUESTION POSTED AT 24/02/2020 - 12:33 AM

How many of the numbers from 10 through 92 have the sum of their digits equal to a perfect​ square?

All the numbers in this range can be written as 10d_1+d_0 with d_1\in\{1,2,\ldots,9\} and d_2\in\{0,1,\ldots,9\}. Construct a table like so (see attached; apparently the environment for constructing tables isn't supported on this site...)

so that each entry in the table corresponds to the sum of the tens digit (row) and the ones digit (column). Now, you want to find the numbers whose digits add to perfect squares, which occurs when the sum of the digits is either of 1, 4, 9, or 16. You'll notice that this happens along some diagonals.

For each number that occupies an entire diagonal in the table, it's easy to see that that number n shows up n times in the table, so there is one instance of 1, four of 4, and nine of 9. Meanwhile, 16 shows up only twice due to the constraints of the table.

So there are 16 instances of two digit numbers between 10 and 92 whose digits add to perfect squares.

ANSWERED AT 24/02/2020 - 12:22 AM


QUESTION POSTED AT 24/02/2020 - 12:22 AM

Pleasee Help!Should've the united states gone to war with Mexico? Provide 2 reasons why or why not.

America wont have a wall next to america and peace would've been made

ANSWERED AT 24/02/2020 - 12:13 AM


QUESTION POSTED AT 24/02/2020 - 12:13 AM

Hank is building a dog run for his dog. He wants the ratio of the length to the width of the dog run to be 5 : 2. If he builds the dog run so the length is 10.5 feet, which equation can be used to solve for the width, x? What is the value of x?

Answer:

The equation is \\ \frac{5}{2} : \frac{10.5ft}{x}; The value of x is 4.2ft.

Step-by-step explanation:

A ratio is like a constant that remains between two values, and we can use it to find whatever others that keep the same constant relation between them.

Hank wants a dog run that keeps a constant relation between length to the width. That is, the length must be 2.5 times to the width ( \\ \frac{5}{2} = 2.5 ).

So, knowing that ratio or constant, we can represent it as follows:

\\ \frac{lenght}{width} : \frac{5}{2} \\ [ 1 ]

But, it also could be expressed as the relation between the width to the length:

\\ \frac{width}{length}:\frac{2}{5} [ 2 ]

He wants a lenght of 10.5ft for building a dog run for his dog, and that this new value must keep the ratio just explained [ 1 ] to the width expected.

So, the equation is:

\\ \frac{5}{2} : \frac{10.5ft}{x}

And we have to find the value for x that solve this equation.

However, we can use an easier way to represent this using the equation [ 2 ] for solving x :

\\ \frac{w}{l} :\frac{2}{5} : \frac{x}{10.5ft} \\\\ x = \frac{2 * 10.5ft}{5}=4.2ft\\

That is, the width must be 4.2ft to keep the ratio length to the width 5:2 ( or the ratio width to the length 2:5).

To check this answer:

\\ \frac{length}{width} : \frac{5}{2} =2.5

\\ \frac{length}{width} = \frac{10.5ft}{4.2ft} = 2.5.

\\ \frac{width}{length} : \frac{2}{5} = 0.4\\

\\ \frac{width}{length} = \frac{4.2ft}{10.5ft} = 0.4.

ANSWERED AT 24/02/2020 - 12:12 AM


QUESTION POSTED AT 24/02/2020 - 12:12 AM

Doreen uses 8 yd of fabric to make 2 costumes. At this rate, how many yards of fabric does she use to make 5 costumes?

You just multiply 8 by 1.5 because 2 × 1.5 = 5 and we need 5 costumes. 8 × 1.5 = 12 yds. I hope this helps!

ANSWERED AT 24/02/2020 - 12:11 AM


QUESTION POSTED AT 24/02/2020 - 12:11 AM

Natalie has to list numbers that are greater than 1. Which of these expressions represent numbers greater than 1?

5x+4=9 its an expression which is greater than 1 you can do almost any expression but it has to be more than one.
Hope this helps :D

ANSWERED AT 24/02/2020 - 12:09 AM


QUESTION POSTED AT 24/02/2020 - 12:09 AM

2 + 6g = 11 - 3g G = ? !!!

G=1 you just ignore the g's and then u say g is 1

ANSWERED AT 24/02/2020 - 12:09 AM


QUESTION POSTED AT 24/02/2020 - 12:09 AM

I have provided a picture for this. I need the answers to #2 a, b, and c!!

The answer is c. Because all you need to know is to find the other leg and find the perimeter of the whole thing.



ANSWERED AT 24/02/2020 - 12:05 AM


QUESTION POSTED AT 24/02/2020 - 12:05 AM

Alice purchased 4 1⁄2 kilograms of olive oil for $27. What is the price per kilogram?

4 1/2 = 9/4 = 4.5 kg
27/4.5=6
The price per kilogram is $6

ANSWERED AT 24/02/2020 - 12:05 AM


QUESTION POSTED AT 24/02/2020 - 12:05 AM

Ethan's school has a sports field with an area of 6,450.35 square yards. If the length of the field is 90.85 yards, what is the width of the field?

Area= Length x Width



A=LxW -----> W=A/L


W= 6,450.35/90.85 
W= 71 ft

ANSWERED AT 24/02/2020 - 12:04 AM


QUESTION POSTED AT 24/02/2020 - 12:04 AM

Can someone PLEASE walk me through this?? Solve by the linear combination method (with or without multiplication). 8x + 2y = 4 –4x + 3y = –10 A. (1, 3) B. (2, 3) C. (1, 2) D. (1, –2)

Here, Multiply second equation by 2, 
-8x + 6y = -20

Now,Add both the equations in order to eliminate x from the expression,
8y= -16
y = -16/8
y = -2

Substitute the value in 1st equation, 
8x + 2(-2) = 4
8x = 4 + 4
x = 8 / 8
x = 1

In short, Your Answer would be Option D) (1, -2)

Hope this helps!

ANSWERED AT 24/02/2020 - 12:04 AM


QUESTION POSTED AT 24/02/2020 - 12:04 AM

If m <2 = 40o then what does m <z equal

Angle x = 180 - (90 + 40) = 50
angle z = 180 - (90+50) = 40

ANSWERED AT 24/02/2020 - 12:04 AM


QUESTION POSTED AT 24/02/2020 - 12:04 AM

Which term describes the polynomial 6 + 3x + 4y? a. cubic trinomial b. constant binomial c. quadratic binomial d.linear trinomial

Answer:

6 + 3x + 4y is a linear trinomial

Step-by-step explanation:

term describes the polynomial 6 + 3x + 4y

a. cubic trinomial must have a variable with cube like x^3 . largest exponent should  be x^3

b. constant binomial have only constant terms

c. quadratic binomial should have x^2 term. largest exponent should be x^2

d.linear trinomial have 3 terms with largest exponent as 1

6 + 3x + 4y is a linear trinomial

ANSWERED AT 24/02/2020 - 12:03 AM


QUESTION POSTED AT 24/02/2020 - 12:03 AM

Simplify the square root: -√64

8i because it's a negative square root

ANSWERED AT 24/02/2020 - 12:03 AM


QUESTION POSTED AT 24/02/2020 - 12:03 AM