Question

sabendo q x+y é igual a 18, calcule x/y=4/5 (com cálculos)

Answer 1

x+y=18 --> x=18-y

x/y=4/5
5x=4y
5(18-y)=4y
90-5y=4y
-5y-4y=-90
-9y=-90
y=-90/-9
y=10

5x=4y
5x=4.10
5x=40
x=40/5
x=8