(x+3)^2 = 49?

(x+3)² = 49
(x+3)² = 7²
x + 3 = |7|
x + 3 = 7 or x + 3 = -7
x = 4 or x = -10

We take the absolute value because number 2 is even so (x+3) can be either a positive or negative number.
E.g: if a² = 4, a = 2 or -2

x + 3 = ± 7
x = - 3 ± 7
x = 4 , x = - 10

x=4 or x=(-10)

(x+3)(x+3) = 49
x^2 + 6x + 9 = 49
X^2 + 6x - 40 = 0
(x-4)(x+10) = 0
thus: x=4.0 ; x= -10.

=D

(x+3)^2=49
sqrt((x+3)^2) = sqrt(49)
x+3 = 7
x = 4

(x + 3)^2 = 49
(x + 3)(x + 3) = 49
x^2 + 3x + 3x + 9 = 49
x^2 + 6x + 9 = 49
x^2 + 6x = 49 - 9
x^2 + 6x = 40
x^2 + 6x - 40 = 0
(x + 10)(x - 4) = 0

x + 10 = 0
x = -10

x - 4 = 0
x = 4

∴ x = -10 or 4

(x+3)^2=49
using(a+b)^2=a^2+2ab+b^2 10*-4=-40
x^2+6x+9=49 10-4=6
x^2+6x+9-49=0
x^2+10x-4x-40
x(x+10)-4(x+10)
(x+10)(x-4)
x+10=0
x=-10 or
(x-4)=0
x=4