X squared plus 2 x equals 15

x2+2x=15

what number should be added to both sides of the equation to complete the square?

Question

Mathematics

Yasmine Torres

28 July, 17:24

X squared plus 2 x equals 15

x2+2x=15

what number should be added to both sides of the equation to complete the square?

+4

Answers (1)

Know the Answer?

Danielle Ramsey · Answer 1

Given

x 2 - 2 x = 15

add 1 to both sides to get:

6 = x 2 -

2 x + 1 = (x - 1) 2

So x - 1 = ± √ 16 = ± 4

Add 1 to both sides to get:

x = 1 ± 4

That is: x = - 3

or

x = 5

X squared plus 2 x equals 15x2+2x=15what number should be added to both sides of the equation to complete the square?

X squared plus 2 x equals 15

x2+2x=15

what number should be added to both sides of the equation to complete the square?