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4 votes
4 votes
What is the solution to Y=-2x²+4x+8
Y=-4x+16

User Forshank
by
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1 Answer

14 votes
14 votes

Hi there!


\large\boxed{(2, 8)}

Solve by setting the two equations equal to each other:

-2x² + 4x + 8 = -4x + 16

Move all terms to one side:

-2x² + 4x + 4x + 8 - 16 = 0

Simplify:

-2x² + 8x - 8 = 0

Factor out a negative 2 from each term:

-2(x² - 4x + 4) = 0

Factor:

-2(x - 2)² = 0

Set the factor equal to 0 to solve:

(x - 2)² = 0

x - 2 = 0

x = 2

Substitute this value of x into an equation to find the shared y value:

y = -4(2) + 16 = 8

User Blablablaster
by
2.8k points