Answer: A. 8x+13
Step-by-step explanation:
9+4(2x-1)+8
Use distributive property
9+8x-4+8
Combine like terms
8x+13
Answer: The mechanics spent about 8.5 hours working on the car
Step-by-step explanation: The total bill was $637, a portion of that being getting the parts which was $280. 637-280=357
357/42=8.5
Without any calculations it's evident it can't be neither B (both numbers are even, so they're divisible by 2) nor C (the numbers end in 0 and 5, so they're divisible by 5).
A.

Both numbers have a factor of 3, so they're not relatively prime.
That means it must be D. But, let's check it.

Indeed, those two numbers are relatively prime.
Answer:
3x -7y = 0
Step-by-step explanation:
Parallel lines have the same slope.
Changing the constant in a linear equation like this only changes the y-intercept. It has no effect on the slope of the line. So, we can change the constant from 4 to 0 and we will have a line with the same slope, parallel to the original, but with a different y-intercept.
The "standard form" of the equation of a line has the leading coefficient positive. We can make that be the case by using the multiplication property of equality, multiplying both sides of the equation by -1.
Parallel line:
-3x +7y = 0
In standard form:
3x -7y = 0