Question

Se stie ca 7a+3b=85 si a=2b.aflati nunerele a si b

Answer 1

$7a+3b=85$

$a=2b$

$7*2b+3b=85$

$14b+3b=85$

$17b=85$

$b= \frac{85}{17}$

$b=5$

$a=2b$

$a=2*5$

$a=10$

Solutia: $a=10$;  $b=5$

Verificare:

$7a+3b=7*10+3*5=70+15=85$