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ratelena [41]
3 years ago
11

64+16x^2-72x+81=289 I don’t understand

Mathematics
1 answer:
7nadin3 [17]3 years ago
7 0

Answer:

x = 6 or x = -3/2

Step-by-step explanation:

Solve for x:

16 x^2 - 72 x + 145 = 289

Hint: | Write the quadratic equation in standard form.

Divide both sides by 16:

x^2 - (9 x)/2 + 145/16 = 289/16

Hint: | Solve the quadratic equation by completing the square.

Subtract 145/16 from both sides:

x^2 - (9 x)/2 = 9

Hint: | Take one half of the coefficient of x and square it, then add it to both sides.

Add 81/16 to both sides:

x^2 - (9 x)/2 + 81/16 = 225/16

Hint: | Factor the left hand side.

Write the left hand side as a square:

(x - 9/4)^2 = 225/16

Hint: | Eliminate the exponent on the left hand side.

Take the square root of both sides:

x - 9/4 = 15/4 or x - 9/4 = -15/4

Hint: | Look at the first equation: Solve for x.

Add 9/4 to both sides:

x = 6 or x - 9/4 = -15/4

Hint: | Look at the second equation: Solve for x.

Add 9/4 to both sides:

Answer:  x = 6 or x = -3/2

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Answer:

C=75t+100

Step-by-step explanation:

Let

C(t) ---->the total cost of the electrician's services in dollars

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we know that

The linear function in slope intercept form is equal to

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In this problem we have

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2m=150

m=\$75\ per\ hour

The linear function is equal to

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4 0
3 years ago
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NEED HELP ASAP!!!!!!!
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I think the answer is C
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Last year there were 221 students and 13 teachers at Hillard School. This year there are 272 students. The principal wants to ke
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Answer:

see explanation

Step-by-step explanation:

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