Question

Teorema de Tales
x/x+3 = 10/15

Answer 1

$\frac{x}{x+3}= \frac{10}{15} \\15x = 10 (x+3)\\15x = 10x + 30\\15x - 10x = 30\\5x = 30\\x = \frac{30}{5} \\x = 6$

Answer 2

\frac{x}{x+3}= \frac{10}{15} \\15x = 10 (x+3)\\15x = 10x + 30\\15x - 10x = 30\\5x = 30\\x = \frac{30}{5} \\x = 6