SOLUTION: -3x^2 +7x = 0

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Question 303850: -3x^2 +7x = 0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

-3x%5E2%2B7x=0 Start with the given equation.


Notice that the quadratic -3x%5E2%2B7x is in the form of Ax%5E2%2BBx%2BC where A=-3, B=7, and C=0


Let's use the quadratic formula to solve for "x":


x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29 Start with the quadratic formula


x+=+%28-%287%29+%2B-+sqrt%28+%287%29%5E2-4%28-3%29%280%29+%29%29%2F%282%28-3%29%29 Plug in A=-3, B=7, and C=0


x+=+%28-7+%2B-+sqrt%28+49-4%28-3%29%280%29+%29%29%2F%282%28-3%29%29 Square 7 to get 49.


x+=+%28-7+%2B-+sqrt%28+49-0+%29%29%2F%282%28-3%29%29 Multiply 4%28-3%29%280%29 to get 0


x+=+%28-7+%2B-+sqrt%28+49+%29%29%2F%282%28-3%29%29 Subtract 0 from 49 to get 49


x+=+%28-7+%2B-+sqrt%28+49+%29%29%2F%28-6%29 Multiply 2 and -3 to get -6.


x+=+%28-7+%2B-+7%29%2F%28-6%29 Take the square root of 49 to get 7.


x+=+%28-7+%2B+7%29%2F%28-6%29 or x+=+%28-7+-+7%29%2F%28-6%29 Break up the expression.


x+=+%280%29%2F%28-6%29 or x+=++%28-14%29%2F%28-6%29 Combine like terms.


x+=+0 or x+=+7%2F3 Simplify.


So the solutions are x+=+0 or x+=+7%2F3