one pump, let's call it A, fills the reservoir by 1/60 every hour. Now, B fills it by 1/80 every hour. C empties it by 1/90 every hour. All three are on, so now we combine them into one function: t(1/60 + 1/80 - 1/90) = 1, where t = the time it takes to fill it, and 1 is just our "reservoir finally filled" marker.
isolate t onto one side and we see t = 720/13 exactly, or approximately 55.38 hours. let me know if this is the wrong answer but I'm pretty sure it is correct!
Answer:

Step-by-step explanation:
<em><u>The formula for finding the area of a triangle is:</u></em>
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<em><u>The "b," is the base (7), and the "h," is the height (8):</u></em>


28
Answer:
x = 2/3
Step-by-step explanation:
9x2−12x+4=0
Step 1: Factor left side of equation.
(3x−2)(3x−2)=0
Step 2: Set factors equal to 0.
3x−2=0 or 3x−2=0
x= 2
/3
Answer:
see below
Step-by-step explanation:
9 dollars / 33 lbs = .272727 dollars per lb
.39 / 1 lbs = .39 per lb
The large bag is less expensive
Rx - sx + y = b
WHEN SOLVING FOR X :
rx - sx + y = b
We must get x onto it's own side, so subtract y from both side.s
rx - sx = b - y
Then, factor out x.
x(r - s) = b - y
Then, divide both sides by (r - s).
x(r - s) ÷ (r - s) = b - y ÷ (r - s)
Simplify.
x = b - y / r - s →

WHEN SOLVING FOR Y :
rx - sx + y = b
We need to isolate y, so get rid of everything BUT y on the left side.
Subtract rx from both sides.
-sx + y = b - rx
Then, add sx to both sides.
y = b - rx + sx
~Hope I helped!~