Question

How to solve y= 2x-1 y= 3x+2 by substitution

Answer 1

(-3, -7).

Explanation:

1. Write the expressions.

`(1)y= 2x-1\\ \\ (2)y= 3x+2`

2. Write equation 1 and substitute its y value by the argument of expression 2.

`(3x+2)= 2x-1\\ \\3x+2= 2x-1`

3. Subtract 2 in both sides of the equation.

`3x+2-2= 2x-1-2\\ \\3x=2x-3`

4. Subtract 2x from both sides of the equation.

`3x-2x=2x-3-2x\\ \\x=-3`

5. Verify the answer.

To see of the answer is correct, both of the equation should give the same y value for the x value of -3.

`(1)y= 2(-3)-1\\ \\ y=-6-1\\ \\y=-7`

`(2)y= 3(-3)+2\\ \\y=-9+2\\ \\y=-7`

6. Express the final result.

(x, y)

(-3, -7).