Step-by-step explanation:
x+y=7 _ eqn1
x-y=3_ eqn2
add eqn1 and eqn2
x+y=7
+ x-y=3
= 2x= 10
x=5
x+y=7
5+y=7
y=7-5
y=2 proved
Lets start with finding the volume of the pool
The formula for the volume of a rectangular prism is
V=l*w*h where l=length w=width and h=height
plug in the data we know
V=40*20*4
V=3200ft³
Now for the hot tub.
3200ft³*1/4=800ft³
Add the volumes together
3200+800=4000ft³
Answer=4000ft³
You would first make an equation to show their individual price per hour multiplied by hours worked then added together to equal total cost. let X be mechanic 1 and Y be mechanic 2
10x + 5y = 1225
the second equation will use their price per hour added together to equal combined cost per hour
x + y = 180
you would solve by substitution. to do so, isolate either x or y in the second equation. for convenience, I will isolate x
x = 180 - y
plug in (180 - y) for x in the first equation
10(180-y) + 5y = 1225
1800 - 10y + 5y = 1225
-5y = -578
y = 115.6
this means that the second mechanic charges $115.60 per hour
to find the price per hour for the first mechanic, plug in (115.6) for y in the second equation
x + 115.6 = 180
x = 64.4
the first mechanic charges $64.40 an hour
For the first roll, you expect that you would get number 3 of a die.
Next for the second roll, you expect that you would get an even number. Since there are 6 sides of a die, so the even numbers are only 2, 4 and 6.