substitution method for 6x-3y=18, and y=2x-6, and show steps

Question

I need assistance in answering the question; how would I use the substitution method to solve the system linear equation of 6x-3y=18, and y=2x-6.

Answer 1

Substitution Method :

The system of equations are 6x - 3y = 18 and y = 2x - 6.

Step 1 : The equation 2 : y = 2x - 6 is already solved for y.

Step 2 : Substitute 2x - 6 for y in the equation 1 : 6x - 3y = 18 to find the value of x.

6x - 3(2x - 6) = 18

Apply distributive property : a(b - c) = ab - ac.

6x - 6x + 18 = 18

18 = 18.

The above statement is true, so the system of equations has infinitely number of solutions.