They are basically like groups. Take -3x+2x , Just do -3 +2 = -1 and then just add the x. So -1x. Next you have -5y+10y . Just do -5 + 10 = 5 and remember to add the x on so your final answer should be -1x + 5y
So first calculate root of 3 which is 1.732
Next multiply by 8 to get 13.856
Hope this helps:)
At the end of 4 years you will pay a extra 240 dollars