Solve the simaltaneous equations: 3x + 4y = 10, 2x + 3y = 7
Solving by elimination
1. multiply the equations by a number so that the number in front of either x or y is the same for both equations:
3x + 4y = 10 (X2) --> 6x + 8y = 20
2x + 3y = 7 (X3) --> 6x + 9y = 21
2. now one of the equations can be subtracted from the other to "eliminate" the x value:
(6x - 6x) + (8y - 9y) = 20 - 21 -y = -1 y = 1
3. substitute in the found value of y into either equation to find the x value:
2x + 3(1) = 7
2x + 3 = 7
2x = 4
x = 2
ST
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