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Find (f+g)(x) and (f-g)(x)
f(x)=2x+7 g(x)=5x-4

User Mogoh
by
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1 Answer

11 votes

Answer:

for (f+g)(x): 7x + 3; x = -3/7

for (f-g)(x): -3x - 3; x = -1

Explanation:

(f+g)(x) = (2x+7)+(5x-4)

Eliminate parentheses.

2x + 7 + 5x -4

Combine like terms.

7x + 3

If you are solving for x, move the 3 to the other side.

7x = -3.

Then divide each side by 7.

x = -3/7

(f-g)(x) = (2x+7) - (5x -4)

Distribute the negative.

(2x+7) + (-5x+4)

Eliminate parentheses.

2x + 7 - 5x - 4

Combine like terms.

-3x -3

If you are solving for x, move the -3 to the other side.

-3x = 3

Then divide each side by -3.

x = -1.

User Xentek
by
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