SOLUTION: Solve the following equation 1. 3x^2=2a 2. X^2-3x-15=0

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Question 1046797: Solve the following equation 1. 3x^2=2a
2. X^2-3x-15=0
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
1) From 3x^2=2a, we divide by 3 and get
x^2 = (2/3)a
then take the square root and get
x = %2B-sqrt%282a%2F3%29
which can be simplified by rationalizing...
2) For x^2 - 3x - 15 = 0, we will have to use the quadratic formula, since it isn't factorable...we get
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%283+%2B-+sqrt%289+-+4%2A1%2A%28-15%29%29%29%2F2+
x+=+%283+%2B-+sqrt%2869%29%29%2F2