Question

1. 2x-y=2 3x+y=8 2. 4x+y=3 3x-y-11 3. 4x-3y=3 4x-7y=-5

Answer 1

1. 2x-y=2

3x+y=8

 

2x-y=2

y=2x-2

3x+y=8

3x+2x-2=8 

5x-10=0

x=10/5
x=2

2x-y=2
2*2-y=2

y=2

 

2. 4x+y=3

3x-y=11

 

4x+y=3
y=-4x+3

3x-y-11
3x-(-4x+3)=11

7x-14=0

x=14/7
x=2

4*2+y=3 

y=-5

 

3. 4x-3y=3

4x-7y=-5

 

4x-3y=3

y=-(-4x+3)/3

4x-7y=-5

4x-7*(-(-4x+3)/3)=-5

-16/3x+12=0

x=12/(16/3)
x=2.25

4x-3y=3
4*(2.25)-3y=3

6-3y=0 

y=6/3

y=2