Solve the simultaneous equations: 5x + 3y = 41 and 2x + 3y = 20 Do not use trial and error.

  1. 5x + 3y = 41   2) 2x + 3y = 20 Subtract equation 2) from equation 1) to cancel the y's (3y-3y = 0) .  Next we subtract  the x's (5x - 2x = 3x) and then finally we have 41 - 20 = 21. We now have that 3x = 21 ( remember both the y's have cancelled) so we can divide both sides by 3 to find that; x = 7
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