Solve the following simultaneous equations: (1) 3x – 2y = 7 (2) 5x + 2y = 17
When looking at the two equations we can see that the 'y' terms in both equations are the same, but with the opposite sign. This means that by adding the two equations we can eliminate the 'y' values.
Step 1: (1) + (2)
3x - 2y = 7 + [5x + 2y =17]
= 8x = 24therefore: x = 3
Step 2: substitute x = 3 into either of the original equations (1) or (2)
(1) 3 (3) - 2y = 79 - 2y = 7.
Step 3: rearrange to find y
9 - 7 = 2y2 = 2yy = 1
answers: x = 3, y = 1
MF
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