Answer:
Step-by-step explanation:
Answer:
Answer choice B.
Step-by-step explanation:
Remember the 3:4:5 rule.
Answer:
17
Step-by-step explanation:
f(5)=3*5+2 where X is equal to 5
Answer:
20 mph
Step-by-step explanation:
Let speed of Train a = Va mph
Let speed of Train b = Vb mph
Va = Vb + 30
Let time taken for Train a = Ta
Let time taken for Train b = Tb
time taken = distance travelled/speed
Ta = 350/Va = 350/(Vb+30)
Tb = 140/Vb
But they both travel in the same amount of time.
So, Ta = Tb
![\frac{350}{v_{b} + 30}=\frac{140}{v_{b}}](https://tex.z-dn.net/?f=%5Cfrac%7B350%7D%7Bv_%7Bb%7D%20%2B%2030%7D%3D%5Cfrac%7B140%7D%7Bv_%7Bb%7D%7D)
Cross multiply
![350v_{b} = 140(v_{b} + 30)\\\\350v_{b} = 140v_{b} + 4200\\\\350v_{b} -140v_{b} = 4200\\\\210v_{b} = 4200](https://tex.z-dn.net/?f=350v_%7Bb%7D%20%3D%20140%28v_%7Bb%7D%20%2B%2030%29%5C%5C%5C%5C350v_%7Bb%7D%20%3D%20140v_%7Bb%7D%20%2B%204200%5C%5C%5C%5C350v_%7Bb%7D%20-140v_%7Bb%7D%20%3D%204200%5C%5C%5C%5C210v_%7Bb%7D%20%3D%204200)
Divide both sides by 210
![\frac{210v_{b} }{210} \frac{4200}{210} \\\\v_{b} = 20 mph](https://tex.z-dn.net/?f=%5Cfrac%7B210v_%7Bb%7D%20%7D%7B210%7D%20%5Cfrac%7B4200%7D%7B210%7D%20%5C%5C%5C%5Cv_%7Bb%7D%20%3D%2020%20mph)