Question

A parabola has a vertex of (3,-2) and a y intercept of 7. what is the equation of this parabola

Answer 1

Explanation:

y=ax^2+bx+c

when x=0,y=7 so c=7

when x=3 then y=a*3^2+b*3+7=-2

9a+3b+7=-2

9a+3b=-2-7

9a+3b=-9

V(3,-2)

3=-b/2a

-b=3*2a

b=-6a

9a+3*(-6a)=-9

9a-18a=-9

-9a=-9

a=1

b=-6*1

b=-6a

b=-6

so y=x^2-6x+7