a) x² + 3² = 5²
x² = 5² - 3²
x² = 25 - 9
x² = 16
x = √16
x = 4b) 25² - x² = 7²
- x² = - 25² + 7²
x² = 625 - 49
x = √576
x = 24
c) 2x² - x² = - 13 - 12
x² = - 25
x = - √25
x = - 5
d) x = 4 + x
1 - x x - 3
x(x - 3) = (4 + x)(1 - x)
(1- x)(x - 3) (1 - x)(x - 3)
x² - 3x = 4 - 4x + x - x²
2x² - 6x = 4
2x (x - 3) = 4
2x = 4
x = 2
x - 3 = 0
x = 3
e) 4(x² + 3x) = 3(x² + 4x)
4x² + 12x - 3x² - 12x = 0
x² =0
f) x - 1 = 2(x - 1) - 2
x x - 1
(x - 1)(x - 1) = 2x(x - 1) - 2x
x² - 2x + 1 = 2x² - 2x - 2x
- (x² + 2x) = - 1
x(x + 2) = 1
x = 1
x + 2 = 0
x = - 2
