Answer:
Step-by-step explanation:
Gradient
Equation of a line
- Sub one set of points into equation
Answer
about 4 hours and 20 minutes
Step-by-step explanation:
200 divided by 60 is 3.33 or 3 hours and 20 minutes, plus the extra hour
S=d/t ⇒d=s*t
s=speed
d=distance
t=time
The first train :
d=x
x=70 miles/h*t ⇒ x=70t (1)
The second train
d=360 miles - x
360 miles - x=80 miles/h*t ⇒360-x=80t ⇒ x=360-80t (2)
therefore, with the equations (1) and (2) we have a systeme of equations:
x=70t
x=360-80t
we can solve this system of equations by equalization method.
70t=360-80t
70t+80t=360
150t=360
t=360/150=2.4 (≈2 hour 24 minutes)
Answer: the first train meet with the second train in 2 hour 24 minutes.
(f+g)(3)=f(3)+g(3)
f(x)=7 so f(3)=7
g(x)=x+5 so g(3)=3+5=8
(f+g)(3)=f(3)+g(3)=7+8=15
