Question

Find a so that the point (-1,2) is on the graph of f(x)=ax^2+5

Answer 1

(x,y) = (-1,2)

so x = -1 and y = 2

Answer 2

f(x)=ax^2+5

y = a*x^2 + 5

2=a*(-1)^2+5 ... plug in x = -1 and y = 2

2 = a*1 + 5

solve for 'a'

Answer 3

-3?

Answer 4

yep