SOLUTION: what is the quadratic formula r squared-10r=39

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Question 422181: what is the quadratic formula r squared-10r=39
Found 2 solutions by mananth, rfer:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
r squared-10r=39
r^2-10r-39=0
a= 1 , b =-10 , c = -39 .
b^2-4ac=256
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29

x1=%2810%2Bsqrt%28256%29%29%2F%282%29
x1=13
...
x2=%2810-sqrt%28256%29%29%2F%282%29
x2=-3

Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
r^2-10r-39=0
a=1, b=-10, c=-39
(10+-sqrt100-4*1*-39)/2
(10+-sqrt256)/2
(10+-16)/2
26/2=13 (13,0)
-6/2=-3 (-3,0)
axis=5
vertex= (5,-64)
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