SOLUTION: r2-10r=-17 plz help me...

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Question 1040301: r2-10r=-17
plz help me...
Found 2 solutions by ikleyn, jorel555:
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
r2 - 10r = -17
plz help me...
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r2+-+10r = -17,

r2+-+10r+%2B17 = 0.

Apply the quadratic formula. See the lessons

    - Introduction into Quadratic Equations

    - PROOF of quadratic formula by completing the square

in this site.

r%5B1%2C2%5D = %2810+%2B-+sqrt%2810%5E2+-+4%2A1%2A17%29%29%2F2 = %2810+%2B-+sqrt%2832%29%29%2F2 = %2810+%2B-+4%2Asqrt%282%29%29%2F2 = 5+%2B-+2%2Asqrt%282%29.


Answer by jorel555(1290) About Me  (Show Source):
You can put this solution on YOUR website!
r2-10r=-17
r2-10r+17=0
Using the quadratic formula, ar2+br+c, we get;
r=7.828, 2.1716 ☺☺☺