Answer:
Step-by-step explanation:
we have that

Using a graph tool
see the attached figure
The function represent a vertical parabola that open up
the vertex is a minimum-------> is the point (-0.5, -9.3)
The x-intercepts are the points when the y coordinate is equal to zero
The x-intercepts are the points (-3.5, 0) and (2.5, 0)
so
the function cross the negative x-axis at point
therefore, the answer is
(-4, 0) and (-3, 0)
I thought this would be simple, as I'm familiar with algebra and not really "The constant of proportionality," but I will do my best.
So this said "Constant of proportionality," is referring to basically the answers for the equation when X equals certain numbers.
Make a table of different answers when you plug in X and you get the 'Constant of proportionality.'
y = 2.5x + 3
y = 2.5(1) + 3
y = 2.5 + 3
y = 5.5
Since we plugged in 1 for X and got 5.5 for Y, our input and output is (1, 5.5)
Replace X for a different value, and you will get a bunch of different numbers that will in essence be your function inputs and outputs. Make a table of these and you have your answer.
EXAMPLE -
-= x =- -= y =-
-= 1 =- -= 5.5 =-
-= 2 =- -= 8 =-
-= 3 =- -= 11.5 =-
-= 4 =- -= 13 =-
So there you have it. I hope this helps! If you have any further questions, don't hesitate to ask.
18 miles = 30 minutes
? miles = 10 minutes
cross multiply
? x 30 = 18 x 10 (180)
? = 180/30
? = 6
the city bus would cover 6 miles in 10 minutes.