Answer:
5x+0.50y=20
Explanation:
A linear equation is an easier way to find a standard equation because it makes it easy to find x and y. So the equation would have to have x and y in it and this problem is 5 and 50 cents and his parents gave him the total which is 20 dollars so the equation would be
5x+0.50y=20
I am in middle school sorry if the explantion is bad