Answer:
10 minutes on stationary bike
30 minutes on elliptical trainer
Explanation:
set up a system of equations:
8t+6b=300
t+b=40
*let t represent elliptical trainer, and let b represent stationary bike
solve by substitution:
8t+6b=300
t=40-b
8(40-b)+6b=300
320-8b+6b=300
-2b=-20
b=10
so, you should spend 10 minutes on the stationary bike
to find how long you should spend on the elliptical trainer:
t=40-b
t=40-10
t=30
so, you should spend:
10 minutes on stationary bike
30 minutes on elliptical trainer