I do one for you but you have to promise me to try the other three.Originally Posted by Aarxn
These are your equations,
There five ways to solve these problem.
I will only mention two which I believe you should know: addition method, substitution method.
Add the two equations, note that , ,
from here divide both sides by three,
The entire purpose of the addition method is when you add your equation you eliminate one of the variables and are left with one.
Solve and equation for any variable, i.e. first equation for 'x' thus,
Now substitute that into the second equation,
, you substituted 'x' for 'y' and hence eliminated a variable.
Subtract 66 and combine 'y' to get,
divide by (-3) to get,