Answer:
x = - 12, y = 9
Step-by-step explanation:
Given the 2 equations
3x + 6y = 18 → (1)
x + 3y = 15 → (2)
Multiplying (2) by - 3 and adding to (1) eliminates the term in x
- 3x - 9y = - 45 → (3)
Add (1) and (3) term by term to eliminate x
- 3y = - 27 ( divide both sides by - 3 )
y = 9
Substitute y = 9 into either of the 2 equations and evaluate for x
Substituting into (2)
x + 3(9) = 15
x + 27 = 15 ( subtract 27 from both sides )
x = - 12
Solution is (- 12, 9 )