SOLUTION: Find b and c so that y= -20x^2 +bx +c has vertex (-5,-3). Thanks, i already know that b= -200 but wasnt sure how to get c

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Find b and c so that y= -20x^2 +bx +c has vertex (-5,-3). Thanks, i already know that b= -200 but wasnt sure how to get c       Log On


   

Question 503831: Find b and c so that y= -20x^2 +bx +c has vertex (-5,-3). Thanks, i already know that b= -200 but wasnt sure how to get c





Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Find b and c so that y= -20x^2 +bx +c has vertex (-5,-3). Thanks, i already know that b= -200 but wasn't sure how to get c
:
So you have -20x^2 - 200x + c = y
Replace x and y
-20(-5^2) - 200(-5) + c = -3
-500 + 1000 + c = -3
500 + c = -3
c = -3 - 500
c = -503