Question

Să se afle numerele a si b stiind ca a supra b egal cu 4 pe 5 si 2a+3b=46

Answer 1

$\frac{a}{b} = \frac{4}{5}$

$5a = 4b$

$a = \frac{4b}{5}$

$2a + 3b = 46$

$2 \times \frac{4b}{5} + 3b = 46$

$\frac{8b}{5} + 3b = 46 \: | \times 5$

$8b + 15b = 230$

$23b = 230$

$b = \frac{230}{23}$

$b = 10$

$a = \frac{4b}{5}$

$a = \frac{4 \times 10}{5}$

$a = \frac{40}{5}$

$a = 8$