SOLUTION: Please help me solve this equation: {{{ 2x^2-16x=-30 }}}

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Question 577108: Please help me solve this equation: +2x%5E2-16x=-30+
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

2x%5E2-16x=-30 Start with the given equation.


2x%5E2-16x%2B30=0 Add 30 to both sides


Notice we have a quadratic equation in the form of ax%5E2%2Bbx%2Bc where a=2, b=-16, and c=30


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-%28-16%29+%2B-+sqrt%28+%28-16%29%5E2-4%282%29%2830%29+%29%29%2F%282%282%29%29 Plug in a=2, b=-16, and c=30


x+=+%2816+%2B-+sqrt%28+%28-16%29%5E2-4%282%29%2830%29+%29%29%2F%282%282%29%29 Negate -16 to get 16.


x+=+%2816+%2B-+sqrt%28+256-4%282%29%2830%29+%29%29%2F%282%282%29%29 Square -16 to get 256.


x+=+%2816+%2B-+sqrt%28+256-240+%29%29%2F%282%282%29%29 Multiply 4%282%29%2830%29 to get 240


x+=+%2816+%2B-+sqrt%28+16+%29%29%2F%282%282%29%29 Subtract 240 from 256 to get 16


x+=+%2816+%2B-+sqrt%28+16+%29%29%2F%284%29 Multiply 2 and 2 to get 4.


x+=+%2816+%2B-+4%29%2F%284%29 Take the square root of 16 to get 4.


x+=+%2816+%2B+4%29%2F%284%29 or x+=+%2816+-+4%29%2F%284%29 Break up the expression.


x+=+%2820%29%2F%284%29 or x+=++%2812%29%2F%284%29 Combine like terms.


x+=+5 or x+=+3 Simplify.


So the answers are x+=+5 or x+=+3