Question

SOMEONE HELP!!!!!! 20 POINTS

What is the standard form of the equation of a quadratic function with roots of 3 and −1 that passes through (1, −10)?

y = 2.5x2 − 5x + 7.5
y = 2.5x2 − 5x − 7.5
y = −2.5x2 − 5x + 7.5
y = −2.5x2 − 5x − 7.5

Answer 1

Explanation:

y = a(x-3)(x+1) sub in the given point to calculate 'a'

-10 = a( 1-3)(1+1)

-10 = -4a

a = 2.5

then y = 2.5 ( x-3)(x+1) = 2.5 x^2 -5x -7.5