Question

(5+2x ) (5+2x )×8-5×5×8=192
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Answer 1

(5+2x) (5+2x) x 8 - 5 x 5 x 8 = 192

(5+2x) (5+2x) x 8 -200 = 192

(5+2x) (5+2x) x 8 = 392

(5+2x) (5+2x) = 392 / 8

(5+2x) (5+2x) = 49

5(5+2x) + 2x(5+2x) = 49

25 + 10x + 10x + 4x^2 = 49

4x^2 + 20x + 25 = 49

4x^2 + 20x = 49 - 25

4x^2 + 20x = 24

4(x^2 + 5x) = 24

x^2 + 5x = 24/4

x^2 + 5x = 6

x^2 + 5x - 6 = 0

D = b^2 - 4ac

D = 5^2 - 4(1)(6)

D = 25 - 24

D = 1

x = -b + Root (D) / 2a

x = -5 + root(1) / 2 and -5 - root(1) / 2

x= -5 + 1 / 2 and -5 - 1 / 2

x = -4 / 2 and -6 / 2

x = -2 and -3 ANSWER .