Tentukan nilai x. Bantu ya... kumpul besokk

jawab

a.

(x+7)²+ (x)² = (2x+3)²
x^2 + 14x + 49 + x^2  = 4x^2 + 12x + 9
x^2 - 4x^2 +14x -12x + 49 -9 = 0
-3x^2 + 2x + 40 =0
3x^2 - 2x - 40 = 0
(3x + 10)(x  - 4) = 0
x = -10/3 (tolak) krn x < 0
x = 4

2
(3x)^2 +(3x-1)^2 = (4x+1)^2
9x^2 + 9x^2 - 6x  +1 = 16x^2 +8x + 1
9x^2 +9x^2 -16x^2 - 6x -8x  =0
2x^2 - 14 x =0
2x(x - 7)= 0
x = 0 (tolak)
x = 7