Answer:
10x + 15y = 980
Step-by-step explanation:
Here, x represents the number of basic washes and y represents the number of ultimate washes,
Since, the charge is $10 per basic wash and $15 per ultimate wash.
So, the total charges = ( 10x + 15y ) dollars
According to the question,
Total charge is $ 980,
⇒ 10x + 15y = 980
which is the required equation.