Answer: 
Step-by-step explanation:
Add 4 to both sides
Divide through by 7
Therefore :
X+4=-4
3x-8=-8
Hope it helps.
Percentage of discount given to senior citizens for tune-ups at the gas station = 20%
Average number of senior citizens visiting the gas station per month = 50
Average price of tune-up before discount = $49.95
Total amount that would
have been collected before discount = 49.95 * 50
= 2497.50 dollars
Total amount of discount given = (20/100) * 2497.50
= 499.50 dollars
I hope that the procedure is clear enough for you to understand.
