SOLUTION: solve for x 9x^2-28=0

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Question 680502: solve for x
9x^2-28=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Use the quadratic formula to solve for x

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

x+=+%280%2B-sqrt%28%280%29%5E2-4%289%29%28-28%29%29%29%2F%282%289%29%29 Plug in a+=+9, b+=+0, c+=+-28

x+=+%28%22%22%2B-sqrt%280-%28-1008%29%29%29%2F%2818%29

x+=+%28%22%22%2B-sqrt%280%2B1008%29%29%2F%2818%29

x+=+%28%22%22%2B-sqrt%281008%29%29%2F18

x+=+%28sqrt%281008%29%29%2F18 or x+=+%28-sqrt%281008%29%29%2F18

x+=+%2812%2Asqrt%287%29%29%2F18 or x+=+%28-12%2Asqrt%287%29%29%2F18

Exact Solutions: x+=+%282%2Asqrt%287%29%29%2F3 or x+=+%28-2%2Asqrt%287%29%29%2F3

Approximate Solutions: x+=+1.763834 or x+=+-1.763834