Distance = Average speed * Time = 48*10 = 480 miles
So, they drove for 480 miles

I'm not sure why ± that sybol isn't working
all together you can write

Ughh just ignore the "A" symbol .-.
Answer: The slope of the line that passes through (2, 12) and (4, 20) is 4.
The value of the y-intercept is 9.
Step-by-step explanation:
Slope of line passing through (a,b) and (c,d) = 
Then, the slope of the line that passes through (2, 12) and (4, 20) = 

So, the slope of the line that passes through (2, 12) and (4, 20) is 4.
To find the y-intercept of 3x + 2y = 18, first write in slope intercept form y=mx+c ( where c= y-intercept ).

By comparison, c= 9
Hence, the value of the y-intercept is 9.
(a) Truck carries 90 gallons of diesel fuel to 660 miles.
So, 1 gallon of diesel fuel to 660/90 = 22/3 miles.
30 gallons of diesel fuel to = 220 miles.
Hence, if x-axis represents the number of miles and y-axis represents the number of gallons, then, (660, 90) and (220, 30) are points on the graph.
Join (660, 90) and (220, 30), we get the graph of a line.
Note that (0, 0) is also a point on the line.
Equation of the line is .
(b) x represents the number of miles. Therefore, the possible values for x is the closed interval [0, 660].
Hence, the domain of the function is [0, 660].
(c) Origin represents that the truck is not moving and there is no diesel fuel loaded in the truck.