20/9 is the answer that I got
Let car b be travelling at x mph. as they are travelling towards each other their speed of approach is (x + x + 15 ) mph. So we have the equation
speed = distance / time
2x + 15 = 250 / 2
2x = 125 - 15 = 110
x = 55 mph
Car b travels at 55 mph and car a travels at 70 mph Answer
Answer:
Total length of the first swing=64 m
Step-by-step explanation:
The total length of all four swings can be expressed as;
Total length of all 4 swings=Length of first swing+length of second swing+length of third swing+length of fourth swing
where;
Total length of all 4 swings=175 m
Length of first swing=x
Length of second swing=75% of length of first swing=(75/100)×x=0.75 x
Length of third swing=75% of length of second swing
Length of third swing=(75/100)×0.75 x=0.5625 x
Length of fourth swing=75% of length of third swing
Length of fourth swing=(75/100)×0.5625 x=0.421875 x
replacing;
Total length of all 4 swings
175=x+0.75 x+0.5625 x+0.421875 x
2.734375 x=175
x=175/2.734375
x=64
Total length of the first swing=x=64 m
Answer: D
Explanation: For this problem you can substitute f(x) and x for 21 and -6 respectively.
Thus, we have 21=-3(-6)+4