Solve by completing the square: x^2 + 2x - 3 =0
a. - 3 or 1
b. X-3 or -1
C. - 3 or -1
d. 2-3 or 1
Please select the best answer from the choices provided

a

Step-by-step explanation:

Given

x² + 2x - 3 = 0 ( add 3 to both sides )

x² + 2x = 3

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(1)x + 1 = 3 + 1

(x + 1)² = 4 ( take the square root of both sides )

x + 1 = ± = ± 2 ( subtract 1 from both sides )

x = - 1 ± 2

Thus

x = - 1 - 2 = - 3

x = - 1 + 2 = 1

correct

step-by-step explanation:

there are 70 more legs than eyes at the dog show (196 – 126 = 70). dogs have two more legs than eyes, and humans have the same number of legs as eyes. thus 70 is twice the number of dogs at the show, so the number of dogs is half of 70, which is 35. to get the number of humans, subtract 35 from 63: 63 – 35 = 28.

step-by-step explanation: