Solve for x and y using these simultaneous equations: 2x + 3y = 21, y = 2x - 1
Substitute y = 2x - 1 into the first equation.
2x + 3(2x -1) = 21
2x + 6x - 3 = 21
8x = 24
x = 3
Therefore y = 2(3) - 1 = 5
AL
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