Your grandma lives 300 miles away. to go to her house, your average is 60 miles per hour(60mph). on the way home, you travel a bit slower at 50 miles per hour (50mph). what was your average speed for the entire round trip?

12cm

the answer is d

step-by-step explanation:

we have

using a graphing tool

see the attached figure

this is a quadratic equation (vertical parabola) open up

the vertex is a > vertex

the domain of the function is all real > interval (-∞,∞)

the range of the function is the > [-6.125,∞)

the function has two x->   and

the function is increasing over the > (0.25,∞)

the function is decreasing over the > (-∞,0.25)

b is the correct answer