SOLUTION: 3x^2+5x=42

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Question 751222: 3x^2+5x=42
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
3x^2+5x=42

3x^2+5x-42 = 0

Use the quadratic formula to solve for x

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

x+=+%28-%285%29%2B-sqrt%28%285%29%5E2-4%283%29%28-42%29%29%29%2F%282%283%29%29 Plug in a+=+3, b+=+5, c+=+-42

x+=+%28-5%2B-sqrt%2825-%28-504%29%29%29%2F%286%29

x+=+%28-5%2B-sqrt%2825%2B504%29%29%2F%286%29

x+=+%28-5%2B-sqrt%28529%29%29%2F6

x+=+%28-5%2Bsqrt%28529%29%29%2F6 or x+=+%28-5-sqrt%28529%29%29%2F6

x+=+%28-5%2B23%29%2F6 or x+=+%28-5-23%29%2F6

x+=+18%2F6 or x+=+-28%2F6

x+=+3 or x+=+-14%2F3

The two solutions are x+=+3 or x+=+-14%2F3