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f(x)=2x^(2)+kx+15, and the remainder when f(x) is divided by x+8 is 95 , then what is the value of k ?

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Answer: k = 6

Step-by-step explanation

The remainder theorem: If p(x) is divided by x-m, then p(m) is the remainder.

The x+8 is the same as x-(-8) to show m = -8.

Plug this into the function so we can solve for k.

f(x)=2x^2+kx+15

f(-8) = 2(-8)^2 + k(-8) + 15

95 = 2(64) - 8k + 15

95 = 128 - 8k + 15

95 = 143 - 8k

143-8k = 95

-8k = 95-143

-8k = -48

k = -48/(-8)

k = 6

Therefore, the function f(x) = 2x^2+6x+15 divided over (x+8) gives some quotient and a remainder of 95.

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