Let's make,
mechanic #1's rate = x
mechanic #2's rate = y
* Their rate is dollars per hour ($/hr)
mechanic #1 worked for 20 hours (hr × $/hr = $)
20x = money earned by mech#1
and mechanic #2 worked for 5 hours
5y = money earned by mech#2
together they charged a total of $1150. So the amount of money earned by both mechanics.
20x + 5y = 1150
the sum of the two rates was $95 per hour.
x + y = 95
which means
x = 95 - y
plug (95 - y) in for "x" in the other equation to get everything in terms of one variable.
20(95 - y) + 5y = 1150
solve for y
1900 - 20y + 5y = 1150
1900 - 15y = 1150
-15y = 1150 - 1900
-15y = -750
y = -750/-15
y = 50 $/hr
Now use this to solve for x
x + y = 95
x + 50 = 95
x = 95 - 50
x = 45 $/hr
mech#1 charged 45$/hr
mech #2 charged 50$/hr
The first and the 2nd one are correct because x is 21 and y is 49
3 and 4 at wrong
Answer:
2A/h - a = b
Step-by-step explanation:
Using A= 1/2(a+b)h
Divide both side by h
⇒A/h = 1/2(a + b)
Mutiply both sides by 2
⇒2A/h = a + b
Take the 2 over to the other side
2A/h - a = b
Keep in mind, that the (a) is not on the bottom, rather on its own
Answer:
3/10
Step-by-step explanation:
(60y-18)=2(8-16)
60y-18=16-16
60y-18=0
60y=18 /:60
y= 18/60=3/10
Answer:
C
Step-by-step explanation:
|2x - 2| < 8
it implies that
2x - 2 < 8
2x -2 + 2 < 8 + 2
2x < 10
x < 5
or
-(2x - 2) < 8
-2x + 2 < 8
-2x + 2 - 2 < 8 - 2
- 2x < 6
x > -3 ( the sense of the inequality reverse because I divided by minus)
The solution can be combine to
-3<x<5