Answer:
C) 20 hours
Step-by-step explanation:
x = number of hours
A yard cleanup service charges a $380 fee plus $14 per hour.
380 + 14x
Another cleanup service charges a $260 fee plus $20 per hour.
260 + 20x
How long is a job for which the two companies' costs are the same?
380 + 14x = 260 + 20x
380 - 260 = 20x - 14x
120 = 6x
20 = x
Answer:
Y=100z
Step-by-step explanation:
Substitute the meters by y and cm by z
1/4 is 25% or 0.25
1/5 is 20% or 0.20
So the difference between the two is 5%, 0.05, or 1/20.
Answer:
Step-by-step explanation:
Ben's car gets between 18 and 21 miles per gallon of gas. If his car's tank holds 15 gallons, it means that the least distance that Ben can drive on one tank of gas would be
18 × 15 = 270 miles.
Also, the most distance that Ben can drive on one tank of gas would be
21 × 15 = 315 miles.
Therefore the the range of distance that Ben can drive on one tank of gas is between 270 miles and 315 miles. If d represents the distance, then the range is
270 ≤ d ≤ 315)
Answer:
A. (3, -3)
Step-by-step explanation:
Let's use the addition/elimination for this to avoid fractions. You could solve one of the equations for y or x and then sub that value into the other equation, but you would have to deal with fractions along the way, so let's just not. Using the addition/elimination (they're the same thing; math books sometimes use one or the other), we line up our equations:
5x + 2y = 9
2x - 3y = 15
It looks like if we want to eliminate the y terms, we can multiply the top equation by 3 and the bottom equation by 2 to get a whole new set of equations:
15x + 6y = 27
4x - 6y = 30
Now we can see that when we add down the columns, the y's cancel each other out. 6y's minus 6y's leaves us with no y's. What we are left with is
19x = 57 so
x = 3.
Now we will sub that 3 back in to either of the original equations to solve for y:
2(3) - 3y = 15 and
6 - 3y = 15 and
-3y = 9 so
y = -3
The solution set then is (3, -3)
