Question

Resolva os sistemas de equaçoes:

h)-28x+24y=0
30x-24y=60

i)x+y=12
x-y=2

j)x+y=60
x-y=12

Answer 1

h)-28x+24y=0
30x-24y=60
2x=60
x=60/2
x= 30
30x-24y=60
30*30-24y=60
90-24y=60
-24y=60-90
-24y=-30
-y = -30+24
-y = -6
y=6




i)x+y=12
x-y=2

2x=14
x=7
x-y=2
7-y=2
-y= 2-7
-y=-5
y=5

j)x+y=60
x-y=12
2x=72
x=72/2
x=36
x-y=12
36-y=12
-y=12-36
-y=-24
y=24