Question

1. Solve this system by substitution.

(y = 3x + 27
y = 4x + 18
2. Solve this system by elimination
(-2x - 4y = -4
2x - 5y = 40
4. Solve this system by substitution
-6x + y = 18
-3x+6y= -24
5. Solve this system by elimination
9x + 21y = 15
-10x + 21y = -61

Answer 1

1. x = 9

2. (10, -4)

4. (-4, -6)

5. (4, -1)

Explanation:

1. Since we know that y = 3x + 27, we can substitute that into y = 4x + 18.

3x + 27 = 4x + 18

9 = x

x = 9

Continue the processes of setting both equations of a system to a specific value, and then substituting it into the other equation.