00:03
All right, we are told that one gym charges only per class.
00:08
There's no monthly fee to join, anything like that.
00:11
So they're only getting charged per class.
00:13
So 7 .5 times x, the number of classes.
00:17
That means basically that every class costs $7 .50.
00:20
That's what this equation would represent.
00:22
Then we have the other one that charges a fee per class as well as a monthly fee.
00:28
But their fee per class is a little less.
00:30
They only charge $5 .50 per class.
00:32
And then $10 per month, no matter how many classes you go to.
00:36
All right.
00:37
And the question asks, for how many classes, is the cost the same? so it looks like you actually already did that part.
00:45
7 .5x equals 5 .5x plus 10.
00:49
We're solving a system of equations using what's called substitution.
00:53
I replaced y with what y was equal to, okay? or vice versa.
00:58
It doesn't matter...