Answer:
Step-by-step explanation:
Givens
d1 = d
d2 = 75 - d
r1 = x
r2 = x + 7
t = 3
Equation
x*t + (x + 7)*t = 75
This equation represents the total distance travelled. Neither one of the cyclists have gone 75 miles, but they both have gone distances that equal a total of 75 miles.
Solution
3x + (x + 7)*3 = 75
3x + 3x + 21 = 75
6x + 21 = 75
6x = 54
6x/6 = 54/6
x = 9
Answer
The first cyclist is going 9 miles / hr
The second cyclist is going 16 miles / hour
