Answer:
Step-by-step explanation:
Begin by transferring the 2 to the right.
x^2 + 8x = 2
Take 1/2 of 8 (which is 4) and square it. (that would make 16). Add that to both sides of the expression
x^2 + 8x + 16 = 2 + 16 Complete the square on the left
(x + 4)^2 = 18 Take the square root of both sides.
sqrt(x + 4)^2 = sqrt(18) Factor 18
sqrt(x + 4)^2 = sqrt(2 * 3 * 3) Take 3 from under the root sign. The other 3 is discarded.
sqrt(x + 4)^2 = 3* sqrt(2) Take the sqrt of the binomial on left.
x + 4 = +/- 3 * sqrt(2) Subtract 4 from both sides
x = - 4 +/- 3*sqrt(2) This is one answer. Find the value of 3*sqrt(2)
x = - 4 +/- 4.2426
x1 = -8.2426
x2 = -0.2426
If you have choices, please list them.
I've listed a graph so that you can see that the answers for the roots are correct. The graph was made by using y = x^2 + 8x - 2 and recording the points where y = 0
