Question

Ajuda alguemmmmm!!!!
X/20=y/15 e x+y=7

Answer 1

X/20=y/15

x/y = 20/15

x/y = 4/3

x+y/y = 4+3/3

7/y = 7/3 ===> y=3....e... x=7-3=4

Answer 2

resolução!

x + y = 7 ___________ x = 7 - y

x/y = 20/15 ÷ 5

x/y = 4/3

7 - y/y = 4/3

4y = 21 - 3y

4y + 3y = 21

7y = 21

y = 21/7

y = 3

x = 7 - y

x = 7 - 3

x = 4

S = { x = 4 e y = 3 }