Answer:
A. y = 1/2 x.
Step-by-step explanation:
Use the point-slope form of a linear (straight line) function:
y - y1 = m(x - x1)
m = 1/2, x1 = 4 and y1 = 2, so:
y - 2 = 1/2(x - 4)
y = 1/2x - 2 + 2
y = 1/2 x (answer)
The slope of the line is 2
Answer:
The first car was traveling 70 mph, while the second was driving 50 mph.
Step-by-step explanation:
Set the cars as a proportion:

X represents the speed of the second car. By cross multiplying, you get the following equation:

You solve by distributing 150 to get 210x = 150x + 3000.
Solving for x gets you 50.
That means the first car was going at 50 mph. Adding 20, you get 70 as the speed for the second car.
Given:
John had to pay a combined electric and gas bill $150.
The electric portion of the bill was $90.
To find:
The ratio of money spent on electric to that on gas.
Solution:
Let x be the amount of gas bill.
The electric portion of the bill was $90 and John had to pay a combined electric and gas bill $150. So,



The gas portion of the bill was $60.
The ratio of money spent on electric to that on gas is:




Therefore, the ratio of money spent on electric to that on gas is 3:2.