Question

Solve the question by substitution method
3x-7y=1;x-y=1

Answer 1

Answer:

therefore by substituting

x=1+y

put in 1st equation

3x-7y=1

3(1+y)-7y=1

3+3y-7y=1

3-4y=1

-4y=1-3

-4y=-2

y=1/2

x=1+y

=1 +1/2=3/2

Answer 2

Answer: x = 3/2

             y = 1/2

           

Step-by-step explanation:

3x-7y=1-------1

x-y=1-------2

Therefore,

From 2 make y subject of formula

x-y=1

y=x-1

Substitute this equation in 1

3x-7(x-1)=1

3x-7x+7-1=0

-4x+6=0

-4x=-6

x=3/2

Replace x=3/2 in y=x-1

y=3/2 -1 which gives 1/2

thus x=3/2 and y=1/2