SOLUTION: {{{ x^2-6x+7=0 }}} how do i get 2 decimals for the answer?

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Question 254013: +x%5E2-6x%2B7=0+
how do i get 2 decimals for the answer?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E2-6x%2B7=0 Start with the given equation.


Notice that the quadratic x%5E2-6x%2B7 is in the form of Ax%5E2%2BBx%2BC where A=1, B=-6, and C=7


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-%28-6%29+%2B-+sqrt%28+%28-6%29%5E2-4%281%29%287%29+%29%29%2F%282%281%29%29 Plug in A=1, B=-6, and C=7


x+=+%286+%2B-+sqrt%28+%28-6%29%5E2-4%281%29%287%29+%29%29%2F%282%281%29%29 Negate -6 to get 6.


x+=+%286+%2B-+sqrt%28+36-4%281%29%287%29+%29%29%2F%282%281%29%29 Square -6 to get 36.


x+=+%286+%2B-+sqrt%28+36-28+%29%29%2F%282%281%29%29 Multiply 4%281%29%287%29 to get 28


x+=+%286+%2B-+sqrt%28+8+%29%29%2F%282%281%29%29 Subtract 28 from 36 to get 8


x+=+%286+%2B-+sqrt%28+8+%29%29%2F%282%29 Multiply 2 and 1 to get 2.


x+=+%286+%2B-+2%2Asqrt%282%29%29%2F%282%29 Simplify the square root (note: If you need help with simplifying square roots, check out this solver)


x+=+%286%29%2F%282%29+%2B-+%282%2Asqrt%282%29%29%2F%282%29 Break up the fraction.


x+=+3+%2B-+sqrt%282%29 Reduce.


x+=+3%2Bsqrt%282%29 or x+=+3-sqrt%282%29 Break up the expression.


So the solutions are x+=+3%2Bsqrt%282%29 or x+=+3-sqrt%282%29


which approximate to x=4.414 or x=1.586