Solve the following simultaneous equations to give a value for both x and y: 3x+3y=9 and 2x+3y=5
- Subtract the bottom equation from the top equation to get 3x-2x=9-5 (you don't see no y values in this equation as the y's have disappeared and cancelled eachother out as 3y-3y=0)2) So 3x-2x=9-5 equals 1x=4 (which is the same as x=4)3) Now we know x=4, substitute this back into one of the equations to find y, shown below: 3x+3y=9 with x substituted in becomes 3(4)+3y=9 which is equal to 12+3y=94) 12+3y=9, bring the +12 across the equals sign to become -12, giving you 3y=9-12 so 3y=-35) If 3y=-3, divide both sides by 3 to give y=-1 6) So the solution is: x = 4, y = -1 which are your two answers to the simultaneous equation :)
AF
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