To determine the price of servicing a car, a mechanic charges a fixed fee plus an hourly
rate for each hour he works. If his price for
4 hours of service is $270, and his price for
7 hours of work is $420, what is the fixed fee
that the mechanic charges?
E. $50
F. $60
G. $70
H. $120

G. $70

Step-by-step explanation:

$420 for 7 hours

$270 for 4 hours

Each of the above already includes the fixed fee.

Now we subtract the bottom line from the top line:

$420 - $270 = $150

$7 hours - 4 hours = 3 hours

$150/3 hours = $50/hour

For 4 hours, the hourly fee is $50/hour * 4 hours = $200.

Since the total charge for 4 hours is $270, then fixed fee is

$270 - $200 = $70

$70

step-by-step explanation:

how many centimeters did the level of the salsa go down by?

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.