Solve the simultaneous equations: 2x+5y=25, x=y+2
using our second equation, we can see that x=y+2. Therefore we can sub x into the first equation. This will give us 2*(y+2)+5y=25. We can go ahead and expand the brackets, which gives us 2y+4+5y=25. We can combine the y terms which gives 7y+4=25. We can take 4 away from both sides with gives 7y=21, and divide both sides by 7 so y=3. We can sub 3 into y in the original equation, to give that x=5.
LW
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