A) 3x + 3y = 27 ----- (1)
x - 3y = -11-------(2)
Multiplying (2) by 3 we have 3x - 9y = -33 ----(3)
Subtracting (3) from (1) we have
-9y - 3y = -33 - 27
So y = 5. Substituting value of y into (1) we have 3x + 3(5) = 27. So x = 27 -
15/ 3 = 4.
B) Also 2x + 4y= 22 ----(1)
2x - 2y= -8 -----(2)
Subtracting (2) from (1) we have
-2y - 4y = -8 - 22 = -30
-6y = - 30. Hence y = 5. Substituting into (1) we have 2x + 4(5) = 22. X = 22 - 20/2 = 1
C) 5x - y = 0 -------(1)
3x + y = 24 ------(2)
Adding (2) to (1) we have
3x + 5x = 24. X = 24/8 = 3. So y = 5(3) - y = 0. y = 15