You multiply both the sides and the top and add them
In order to eliminate the y terms, the y terms must be reciprocals.
The first equation has 9y.
To eliminate y, you need to add to it -9y.
The second equation has y. In order for the second equation to have -9y, you must multiply both sides of the second equation by -9.
Answer: D -9
"Each plan utilizes a combination of 2 strength-training sessions and 2 aerobic exercise sessions per week." because.
Let n be the number of aerobic and strength-training exercises per week.
Let x be the number of strength-training exercises per week on the beginner
15x + 20n = 90
Let y be the number of strength-training exercises for week on the advanced plan.
20y + 30n = 130
Multiply both sides by 1.5, to get:
22.5x + 30n = 135
Subtracting equation 2 from 3 we get:
22.5x - 20y = 5
I believe that the diameter would be "6.5" but I'm not 100% sure.
