first combine like terms so 2n + 7n which is 9n
so 9n + 7 = 13 + 3n + 8n
then combine on other side so 9n + 7 = 13 + 11n
then subtract 7 to 13 so 6
sp 9n + 6 = 11n
then subtract 9 to the other side so 2n
6 = 2n then divide all by 2
n= 3
Answer:
23. 0.4583 seconds
24. 0.0107 seconds
Step-by-step explanation:
The problem statement tells you how to work it. You need to convert speed from miles per hour to feet (or inches) per second.
90 mi/h = (90·5280 ft)/(3600 s) = 132 ft/s = (132·12 in)/s = 1584 in/s
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23. The time it takes for the ball to travel 60.5 ft is ...
time = distance/speed
time = (60.5 ft)/(132 ft/s) = 0.4583 s
It takes 458.3 milliseconds to reach home plate.
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24. time = distance/speed
time = (17 in)/(1584 in/s) = 0.0107 s
The ball is in the strike zone for 10.7 milliseconds.