Question

simplificati fractiile
2x-8/3x-12
b)5x-15/×^2-9
c)×^2-9/×^2-6×+9
d)×^2-10×+21/×^2-9.

Answer 1

$\frac{2x - 8}{3x - 12} = \frac{2(x - 4)}{3(x - 4)} = \frac{2}{3}$

$\frac{5x - 15}{ {x}^{2} - 9 } = \frac{5(x - 3)}{(x - 3) \times (x + 3)} = \frac{5}{x + 3}$

$\frac{ {x}^{2} - 9}{ {x}^{2} - 6x + 9 } = \frac{(x - 3) \times (x + 3)}{(x - 3) {}^{2} } = \frac{x + 3}{x - 3}$

$\frac{x {}^{2} - 10x + 21 }{x {}^{2} - 9 } = \frac{x { }^{2} - 3x - 7x + 21}{(x - 3)(x + 3)} = \frac{x \times (x - 3) - 7(x - 3)}{(x - 3)(x + 3)} = \frac{(x - 3)(x - 7)}{(x - 3)(x + 3)} = \frac{x - 7}{x + 3}$