Answer:
Part A:
y = minutes doing freehand exercises
x = minutes running on the treadmill
Write a pair of linear equations:y + x = 60 (total time at the gym)x = y + 30 (running time is 30 minutes more than freehand time)Part B:
To find the time Jacob spends doing freehand exercises, substitute the value of x from the second equation into the first equation:
y + (y + 30) = 60
2y + 30 = 60
2y = 30
y = 15