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I need help to find the indicated operation:g(x)= -x^2 +4xh(x)= -4x-1Find (3g-h)(-3)

User Henderson
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1 Answer

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We have the following functions:


\begin{gathered} g\mleft(x\mright)=-x^2+4x \\ h\mleft(x\mright)=-4x-1 \end{gathered}

And we need to find:


(3g-h)(-3)

Step 1. Find 3g by multiplying g(x) by 3:


\begin{gathered} g(x)=-x^2+4x \\ 3g=3(-x^2+4x) \end{gathered}

Use the distributive property to multiply 3 by the two terms inside the parentheses:


3g=-3x^2+12x

Step 2. Once we have 3g, we subtract h(x) to it:


3g-h=-3x^2+12x-(-4x-1)

Here we have 3g and to that, we are subtracting h which in parentheses.

Simplifying the expression by again using the distributive property and multiply the - sign by the two terms inside the parentheses:


3g-h=-3x^2+12x+4x+1

Step 4. Combine like terms:


3g-h=-3x^2+16x+1

What we just found is (3g-h)(x):


(3g-h)(x)=-3x^2+16x+1

Step 5. To find what we are asked for


\mleft(3g-h\mright)\mleft(-3\mright)​

We need to evaluate the result from step 4, when x is equal to -3:


(3g-h)(-3)=-3(-3)^2+16(-3)+1

Solving the operations:


(3g-h)(-3)=-3(9)^{}-48+1
(3g-h)(-3)=-27^{}-48+1
(3g-h)(-3)=-74

Answer:


(3g-h)(-3)=-74

User Maksym Fedorov
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