Simultaneous questions: 2x+y=7, 3x-y=8
First of all, you want to get both of the questions equating to y as this is a common factor between the two equations. SO y=7-2x and 3x-8=y As both of the equations are equal to y, we can set them equal to each other. SO 7-2x=3x-8 Now you want to bring all of the common factors together. So x's on one side, integers on the other. 7+8=3x+2x 15=5x We now want to divide both sides by 5 so we know what once x is equal to. 3=x We now fill this back into an equation to find out y 2(3) + y =7 6+y=7 y=7-6 y=1 Therefore, x=3, y=1
BJ
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