SOLUTION: Can you please help me solve this equation of linear functions using the substitution method? 8x - 9y = 24 -2x - 1y = 18 Thank you.

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Can you please help me solve this equation of linear functions using the substitution method? 8x - 9y = 24 -2x - 1y = 18 Thank you.      Log On


   

Question 701143: Can you please help me solve this equation of linear functions using the substitution method?
8x - 9y = 24
-2x - 1y = 18
Thank you.
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
8x - 9y = 24
-2x - 1y = 18
-y=2x+18
y=-2x-18 Now replace y in the first equation with (-2x-18) & solve for x.
8x-9(-2x-18)=24
8x+18x+162=24
26x=24-162
26x=-138
x=-138/26
x=-5.3 ans.
-2(-5.3)-y=18
10.6-y=18
-y=18-10.6
-y=7.4
y=-7.4 ans.
Proof:
8(-5.3)-9(-7.4)=24
-42.4+66.6=24
24.2=24 (not equal due to a rounding error).