Find c so that the parabola y=-13x^2-208x+c has vertex (-8,6)?

Question

I am stuck with finding c.

Answer 1

y = -13x² - 208x + c

Given the vertex (-8, 6)

substitute (x, y) = (-8, 6) in the equation.

6 = -13(-8)² - 208(-8) + c

6 = -13(64) + 1664 + c

6 = -832 + 1664 + c

6 = 832 + c

Subtract 832 from each side.

c = -826

Therefore c = -826.

Comments

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