Answer:
The answer is 75.
Step-by-step explanation:
Average rate of change = Δy/Δx
y^2 - y^1/x^2 - x^1
925 - 400/12 - 5 = 525/7 = 75
Answer:
unclear man, u cant add them together sorry
Step-by-step explanation:
X + 4y = 4
-x + 2y = 8
x + 4y - x + 2y = 4 + 8
6y = 12
y = 2
x + 4(2) = 4
x + 8 = 4
x = -4
(x,y)
(-4,2)
Try this:
1) note that weight of pure antifreeze before mixing and after mixing is the same. So, if 'x' is weight of pure antifreeze in 50% solution, it is possible to make up equation before mixing: 0.5x+0.2*90.
2) there are 0.2*90=18 gal. of pure antifreeze in the 20% solution. If 'x' gal. is the weight of pure antifreeze in 50% sol. and 18 gal. is the weight of pure antifreeze in 20% sol., it is possible to make up an equation after mixing: 0.4(x+18).
3) using the both parts: 0.5x+0.2*90=0.4(x+18) ⇒ x=54 gal. of <u>pure</u> weight.
4) to find 50% solution of 54 gal. pure weight just 54:0.5=108 gal.
Answer: 108 gal.
