Answer:
multiply the second equation by - 2
Explanation:
Given the 2 equations
5c + 4d = 10 → (1)
3c + 2d = 16 → (2)
Multiplying (2) by - 2 and adding to (1) will eliminate d
- 6c - 4d = - 32 → (3)
Add (1) and (3) term by term to eliminate d
- c + 0 = - 22
- c = - 22 ( multiply both sides by - 1 )
c = 22
Substitute c = 22 into either of the 2 equations and solve for d
Substituting into (2)
3(22) + 2d = 16
66 + 2d = 16 ( subtract 66 from both sides )
2d = - 50 ( divide both sides by 2 )
d = - 25
solution is c = 22, d = - 25