SOLUTION: 3x^2+8x=11

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Question 686433: 3x^2+8x=11
Found 2 solutions by jim_thompson5910, markcosta:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
3x%5E2%2B8x=11

3x%5E2%2B8x-11+=+0

Use the quadratic formula to solve for x

x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29

x+=+%28-%288%29%2B-sqrt%28%288%29%5E2-4%283%29%28-11%29%29%29%2F%282%283%29%29 Plug in a+=+3, b+=+8, c+=+-11

x+=+%28-8%2B-sqrt%2864-%28-132%29%29%29%2F%286%29

x+=+%28-8%2B-sqrt%2864%2B132%29%29%2F%286%29

x+=+%28-8%2B-sqrt%28196%29%29%2F6

x+=+%28-8%2Bsqrt%28196%29%29%2F6 or x+=+%28-8-sqrt%28196%29%29%2F6

x+=+%28-8%2B14%29%2F6 or x+=+%28-8-14%29%2F6

x+=+6%2F6 or x+=+-22%2F6

x+=+1 or x+=+-11%2F3

So the two solutions are x+=+1 or x+=+-11%2F3

Answer by markcosta(2) About Me  (Show Source):
You can put this solution on YOUR website!
3x²+8x=11 --> 3x²+8x-11=0 *We equal the equation to zero. Now its a second grade
equation

Applying the second grade solving formula:
x+=+%28-8+%2B-+sqrt%28+64+-+4%2A3%2A%28-3%29+%29%29%2F%282%2A3%29+
x1 = -8 + 6 / 6 = -1/3
x2 = -8 - 6 / 6 = -7/3