Question

Determine the solution to each linear system by using the substitution method

3x+2y=4
2x-y=5

Answer 1

The solution is x = 2

Explanation:

i) 3x+2y=4

ii) 2x-y=5

Let's isolate y for the second equation

2x-y=5

2x-5 = y

y = 2x-5

Now use this y and substitute it in the first equation.

3x+2y=4

3x + 2(2x-5) = 4

3x + 4x - 10 = 4

7x / 7 = 14 / 7

x = 2