Label the equations 1) 5x+5y = 6 and 2) 7x+3y = 6 . Then rearrange equation 1 to make x the subject of the equation: 5x = 6-5y. You would then simplify this equation to find the equation for x: x = 6/5 - y.
Once you have found the equaiton for x you subsitute it back into equation number 2: 7(6/5 - y) + 3y = 6. This equtation then needs to be expanded before it can be simplified to find y: 42/5 - 7y + 3y = 6. This can then be simplified to : 42/5 -4y = 6. You then rearrange to make y the subject of the equation and simplify: 4y = 12/5. then y=3/5. Once you have found this y value you must put it back into the equation you found for x in order to find the value for x: x= 6/5 - 3/5. Therefore the value for x is also 3/5. It is important to check these values for x and y by putting them into either starting equations 1 or 2 and checking that they result in the correct answer.