Question

A quadratic equation has a vertex at (−3/2,7/2) and a y-intercept of 8.

Which equations could describe this quadratic equation?

There is more than one correct answer. Select all that apply.

a) y=(x+32)2+74
b) y=x2+3x+4
c) y=2(x+32)2+74
d) y=x2−3x+7
e) y=2((x+32)2+74)
f) y=2x2+6x+8

Answer 1

given: vertex is (−3/2,7/2) and a y-intercept of 8
so the equation is
y = a(x+3/2)^2 + 7/2
but (0,8) lies on it
8 = a(9/4) + 7/2
times 4
32 = 9a + 14
9a = 18
a = 2
so we have y = 2(x + 3/2)^2 + 7/2
expand and simplify, then see if you find the match
(I found it)