Question

mim ajudem por favor

Answer 1

teorema de Tales:

$b)\\ \frac{3}{5} = \frac{12}{x} \\ 3x = 60 \\ x = \frac{60}{3} = 20$

$c) \\ \frac{3}{4} = \frac{x}{8} \\ 4x = 24 \\ x = \frac{24}{4} = 6$

$d) \\ \frac{21}{12} = \frac{3x + 1}{2x - 2} \\ 12 \times (3x + 1) = 21 \times (2x - 2) \\ 36x + 12 = 42x - 42 \\ 12 + 42 = 42x - 36x \\ 54 = 6x \\ x = \frac{54}{6} = 9$