9x−3y=1

3y=x−1

How do I solve these using substitution?

 

We solve the following using substitution method as follows:

9x - 3y = 1

3y = x-1

using the substitution method, 3y appears from both equations and therefore, we use the second equation and substitute the 3y using the the values in the second equation as follws:

9x - 3y = 1

but the value of 3y is x-1 and therefore, we substitute as follows:

9x - (x-1) = 1

9x - x + 1 = 1

8x = 1-1

8x = 0

x = 0/8

x = 0

we use the second equation to get the value of y as follows:

3y = x-1

3y = 0-1

3y = -1

y = -1/3

and therefore,

x = 0 and y = -1/3