SOLUTION: I am having trouble with this problem I have gotten about half way through and can not figure out the rest. Use the quadratic formula to solve each equation. 900x^2 - 8,100x =

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Question 44696This question is from textbook Intermediate Algebra
: I am having trouble with this problem I have gotten about half way through and can not figure out the rest.
Use the quadratic formula to solve each equation.
900x^2 - 8,100x = 1,800
This is what I have come up with so far, Maybe I am making a mistake that I am overlooking.
900x^2/90 - 8,100x/90 = 1,800/90
10x^2 - 90x = 20
10x^2 - 90x - 20 = 0
+x+=+%5B-%28-90%29%2Bplus_minus-sqrt%28%28-90%29%5E2+-+4%2810%29%28-20%29%29%5D%2F2%2810%29+
+x+=+%5B-%28-90%29%2Bplus_minus-sqrt%288%2C100+%2B+800%29%2F20+
+x+=+%5B-%28-90%29%2Bplus_minus-sqrt%288%2C900%29%2F20+
This is where I have gotten stuck.
I hope this problem is readable, I am having trouble figuring out the right way to type it on here.
Thanks in advance for any help you can provide me. This question is from textbook Intermediate Algebra

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
900x^2 - 8,100x = 1,800
Divide both sides by 900 to get:
x^2-9x=2
x^2-9x-2=0
x=[9+sqrt(81+8)]/2 or x=[9-sqrt(90)]/2
Simplify a little to get:
x=[9+3sqrt10]/2 or x=[9-3sqrt(10)]/2
Cheers,
Stan H.