Question

Tolong jawab pakai cara ya

| x + 1 | + 2 x = 7

Answer 1

(x+1) +2x = 7
x+ 1 + 2x = 7
3x + 1 = 7
3x = 7 - 1
3x = 6
x = 6/3 = 2

- (x+ 1) + 2x = 7
- x - 1 + 2x = 7
x - 1 = 7
x = 7 + 1
x = 8

Answer 2

|x + 1| + 2x = 7
|x + 1| = 7 - 2x
kuadratkan kedua ruas
(x + 1)² = (7 - 2x)²
x² + 2x + 1 = 49 - 28x + 4x²
4x² - x² - 28x - 2x + 49 - 1 = 0
3x² - 30x + 48 = 0
bagi 3 kedua ruas
x² - 10x + 16 = 0
(x - 8) (x - 2) = 0
x = 8 V x = 2

maka penyelesaian persamaan mutlak tersebut yaitu x = 2 dan x = 8