Solve the simultaneous equations 7x - 2y = 22 and 5x + 3y = 29
So we're going to solve this question using the elimination method. Now we can see that none of the x or y terms are the same in the 2 equations, so we have to make them the same. The easiet way to do this would be to find the LCM of the 2 coefficients of x, which is 35.
So:
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7x-2y = 22 (Multiply equation by 5)
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5x+3y = 29 (Multiply equation by 7)
This gives us:
- 35x-10y = 110
4.35x + 21y = 203
Solving equations 3 and 4 using the elimination method gives us y=3. Substituting this value for y into equation 2 gives us x=4.
RB
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