Solve the simultaneous equations; 2x + y = 18; x + 3y = 19.
Start by selecting a variable to eliminate from the equations. --> Select x in this case.Take the second equation and multiply by 2. --> 2x + 6y = 38Subtract the first equation from this answer. --> 5y = 20Divide through by 5. --> y = 4Substitute this back into the second equation to solve for x. --> x = 7Substitute both x = 7 and y = 4 into the first equation as a check. --> 2(7) + 4 = 18 --> 14 + 4 = 18. Correct
MA
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