Answer :
An aerobic lesson will be defined as 'a'
For every member lesson, they pay $4, so they will be represented as 4a
For every non member lesson, they pay $6, so they are 6a
Don't forget members have to pay $8 at the start, so they have to be 4a + 8
So
4a + 8 = 6a is our final equation
Move the 'a's to one side, by subtracting 4a from each side, giving you
8 = 2a
Divide by 2 to isolate a
4 = a
After 4 aerobics classes, the cost will be the same
For every member lesson, they pay $4, so they will be represented as 4a
For every non member lesson, they pay $6, so they are 6a
Don't forget members have to pay $8 at the start, so they have to be 4a + 8
So
4a + 8 = 6a is our final equation
Move the 'a's to one side, by subtracting 4a from each side, giving you
8 = 2a
Divide by 2 to isolate a
4 = a
After 4 aerobics classes, the cost will be the same