SOLUTION: 3x^2+8x+4=0

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Question 635895: 3x^2+8x+4=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

3x%5E2%2B8x%2B4=0 Start with the given equation.


Notice that the quadratic 3x%5E2%2B8x%2B4 is in the form of Ax%5E2%2BBx%2BC where A=3, B=8, and C=4


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-%288%29+%2B-+sqrt%28+%288%29%5E2-4%283%29%284%29+%29%29%2F%282%283%29%29 Plug in A=3, B=8, and C=4


x+=+%28-8+%2B-+sqrt%28+64-4%283%29%284%29+%29%29%2F%282%283%29%29 Square 8 to get 64.


x+=+%28-8+%2B-+sqrt%28+64-48+%29%29%2F%282%283%29%29 Multiply 4%283%29%284%29 to get 48


x+=+%28-8+%2B-+sqrt%28+16+%29%29%2F%282%283%29%29 Subtract 48 from 64 to get 16


x+=+%28-8+%2B-+sqrt%28+16+%29%29%2F%286%29 Multiply 2 and 3 to get 6.


x+=+%28-8+%2B-+4%29%2F%286%29 Take the square root of 16 to get 4.


x+=+%28-8+%2B+4%29%2F%286%29 or x+=+%28-8+-+4%29%2F%286%29 Break up the expression.


x+=+%28-4%29%2F%286%29 or x+=++%28-12%29%2F%286%29 Combine like terms.


x+=+-2%2F3 or x+=+-2 Simplify.


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