Solve the simultaneous equations; 5x + 2y = 11, 4x – 3y = 18
Here you have 2 equations and you need to find the value of x and of y. First we are going to find the value of x. We do this by eliminating the y factor by multiplying and adding the equations. If we multiply EQUATION 1 by 3 and EQUATION 2 by 2, the equations look like; 15x+6y=33, 8x-6y=36. Hence have equal y factors. Adding the equations together we eliminate the y values and have 1 equation that is 23x=69, so x=3. Subbing x=3 into either equations we can find the value of y.
- 5x+2y=11, 5*3+2y=11, 15+2y=11, 2y=-4, y=-2
OR
2.4x-3y=18, 4*3-3y=18, 12-3y=18, -3y=6, y=-2
AC
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