Solve the equation by completing the square: x^2 + 8x = 14?

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to complete the square u just need to divide the second term by 2
and square the answer. so 8/2 =4 and 4^2 = 16

add the 16 on both sides giving u this equation:

x^2 +8x+16 = 14+16

then just write down the square of the sum of square root of 1st term and the square root of last term

(x+4)^2 =30

x+4 = sqrt(30)
x= sqrt(30) -4...Show more

To complete the square, you take the "b" of the quadratic equation:

ax^2 + bx = c

cut it in half, and then square it.

x^2 + 8x = 14
-----> (8/2) = (4)^2 = 16.

Once you have this number, add it to both sides of the equation to "complete the square."

x^2 +8x = 14 <----- Add 16 to both sides
x^2 + 8x + 16 = 30 <---- What do you know! A perfect square trinomial! Factor it.
(x+4)^2 = 30 <--- Square root both sides to isolate "x"
x+4= √30 <---- Minus 4 to solve for x
x= (√30) - 4...Show more

x^2 + 8x + 16 = 14 + 16
(x + 4 )^2 = 30
√(x + 4)^2 = √30
x + 4 = √30
x = 4 - √30...Show more