SOLUTION: Please help solve this ! The question states. Explain each step in your solution. √(3x^2 )+10x-5=0 Thank you

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Question 691072: Please help solve this !
The question states. Explain each step in your solution.
√(3x^2 )+10x-5=0
Thank you
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%283x%5E2%29+%2B+10x+-+5+=+0+
Add 5 and subtract 10x from both sides
sqrt%283x%5E2%29+=+-10x+%2B+5+
Square both sides
%28sqrt%283x%5E2%29%29%5E2 = %28-10x%2B5%29%5E2
FOIL the right side
3x^2 = 100x^2 - 50x - 50x + 25
0 = 100x^2 - 3x^2 - 100x + 25
A quadratic equation
97x^2 - 100x + 25 = 0
Use the quadratic formula to solve this a=97;b=-100;c=25
x+=+%28-%28-100%29+%2B-+sqrt%28-100%5E2-4%2A97%2A25+%29%29%2F%282%2A97%29+
x+=+%28100+%2B-+sqrt%2810000-9700+%29%29%2F194+
x+=+%28100+%2B-+sqrt%28300+%29%29%2F194+
Two solutions
x+=+%28100+%2B+17.32%29%2F194+
x = 117.32%2F194
x = .6047
and
x+=+%28100+-+17.32%29%2F194+
x = 82.68%2F194
x = .4262
:
but only x=.4262 checks out in the original equation:
sqrt%283%2A.4262%5E2%29+%2B+10%28.4262%29+-+5+=+0+
sqrt%28.545%29+%2B+4.262+-+5+=+0+
.7382 + 4.262 - 5 = 0
:
so only x = .4262 is the solution