a.2x+2y=8
2x-3y=-7
2x=8-2y
8-2y-3y=-7
2x=8-2y
-5y=-15 |÷(-5)
2x=8-2y
y=3
2x=8-2*3
y=3
2x=2
y=3
x=1
y=3
b.4y+2x=10
3x+8y=10
4y=10-2x
3x+2(10-2x)=10
4y=10-2x
3x+20-4x=10
4y=10-2x
-x=-10
4y=10-2x
x=10
4y=10-2*10
x=10
4y=-10
x=10
y=-2,5
x=10
c.4a+2b=10
5a-2b=-10
a=(10-2b)÷4=2,5-½b
5(2,5-½b)-2b=-10
a=2,5-½b
12,5-2,5b-2b=-10
a=2,5-½b
-4,5b=-22,5
a=2,5-½b
b=5
a=2,5-2,5
b=5
a=0
b=5
d.5a+8b=14
4a+3b=1
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a+5b=13
a=13-5b
5(13-5b)+8b=14
65-25b+8b=14
-17b=-51
b=3
a=13-5b
a=-2
b=3
e.4(x-2)-(y-2)=1
10x-2y=18
4x-8-y+2=1
10x-2y=18
4x-y=7
10x-2y=18
y=4x-7
10x-2(4x-7)=18
y=4x-7
10x-8x+14=18
y=4x-7
2x=4
y=4x-7
x=2
y=4*2-7
x=2
y=1
x=2
f.2x-4(y+1)=10
2(x+3)-(1-y)=9
2x-4y-4=10
2x+6-1+y=9
2x-4y=14
2x+y=4
y=4-2x
2x-4(4-2x)=14
y=4-2x
2x-16+8x=14
y=4-2x
10x=30
y=4-2x
x=3
y=4-2*3
x=3
y=-2
x=3
