Question

find the vertex of f(x) = 3x^2-30x+72 ....I got (5,-51) but the computer keeps saying thats wrong. what did I do wrong?

Answer 1

x coordinate of vertex = -b/2a = 30/6 = 5
y .............................. = 3*25-150 + 72 = -3

(5,-3)

Answer 2

your x cood was right - error was in calculating y cood

Answer 3

ok?

Answer 4

darn! you're right thanks! i couldn't figure it out!

Answer 5

yw