Question

daca x/3=y/4 si 3x + 4y=75, determinati njmerele x si y.

Answer 1

x=3k
y=4k
3*3k+4*4k=75
9k+16k=75
25k=75
k=75:25
k=3
x=3*3=9
y=4*3=12

Answer 2

$\frac{x}{3} = \frac{y}{4} =\ \textgreater \ x= \frac{3y}{4}$
3*$\frac{3y}{4}+4y=75$
$\frac{9y}{4} +4y=75$
9y+16y=300
25y=300
y=300:35
y=12
x=3*12:4
x=9