okay i need to solve the quadratic y = -x^2 + 5x + 6 and need to find the coordinates of the vertex of the curve(adsbygoogle = window.adsbygoogle || []).push({});

by factorising

y = -(x^2 - 5x - 5)

y = -(x + 1)(x - 6)

so when y = 0, x = -1 and x = 6 (that parts simple)

.........................................................................

At the vertex x = (-1 + 6) / 2 = 5/2 (as the curve is symetrical)

so as y = -x^2 + 5x + 6

y = -5/2^2 + 5(-5/2) + 6

y = 25/4 + 50/4 + 24/4

y = 99/4

(this is the answer i got which doesn't look right, and answer book gives a different answer)

can u tell me where i went wrong? thanx

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# Simple Quadratic Factor question

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