Answer:
You will need 220 mL of the 60% solution and 80 mL of pure alcohol.
Step-by-step explanation:
Let 'x' be the amount of 50% alcohol solution and y the amount of pure alcohol.
Therefore:
(0.5x + y)/300 = 0.65 ⇒ 0.5x + y = 190
x + y = 300
Solving the sistem of equations:
x = 220 and y = 080
Therefore, You will need
220 mL of the 60% solution
and 80 mL of pure alcohol.
So if she fill up 5/8 in 1/4 hours we get this equation :
1/4x = 5/8
divide everything with 1/4
x=5/2
Case a)
f(x)=[x-1]/[x+5]
step 1
f(x)=y
y=[x-1]/[x+5]
step 2
exchange x for y and y for x
y=[x-1]/[x+5]------> x=[y-1]/[y+5]----> x*[y+5]=[y-1]----> xy+5x=y-1
step 3
clear the variable y
xy+5x=y-1-----> y-xy=5x+1----> y*[1-x]=[5x+1]----> y=[5x+1]/[1-x]
step 4
f(x)-1= [5x+1]/[1-x]
the function and the inverse function are not the same
case b)
g(x)=[x-2]/[x-1]
step 1
g(x)=y
y=[x-2]/[x-1]
step 2
exchange x for y and y for x
y=[x-2]/[x-1]------> x=[y-2]/[y-1]----> x*[y-1]=[y-2]----> xy-x=y-2
step 3
clear the variable y
xy-x=y-2-----> xy-y=-2+x----> y*[x-1]=[x-2]----> y=[x-2]/[x-1]
step 4
g(x)-1= [x-2]/[x-1]
the function and the inverse function are the same
case c)
h(x)=[x+3]/[x-2]
step 1
h(x)=y
y=[x+3]/[x-2]
step 2
exchange x for y and y for x
y=[x+3]/[x-2]------> x=[y+3]/[y-2]----> x*[y-2]=[y+3]----> xy-2x=y+3
step 3
clear the variable y
xy-2x=y+3-----> xy-y=3+2x----> y*[x-1]=[2x+3]----> y=[2x+3]/[x-1]
step 4
h(x)-1= [2x+3]/[x-1]
the function and the inverse function are not the same
case d)
k(x)=[x+1]/[x-1]
step 1
k(x)=y
y=[x+1]/[x-1]
step 2
exchange x for y and y for x
y=[x+1]/[x-1]------> x=[y+1]/[y-1]---> x*[y-1]=[y+1]----> xy-x=y+1
step 3
clear the variable y
xy-x=y+1-----> xy-y=x+1----> y*[x-1]=[x+1]----> y=[x+1]/[x-1]
step 4
k(x)-1= [x+1]/[x-1]
the function and the inverse function are the same
Answer:
4,260 feet below sea level (-4,260 feet)
Step-by-step explanation:
The submarine starts at sea level which should be 0 for elevation. And descending 7 feet per second for 2 minutes which means it went down 840 feet ( 7x60x2). Then 4 feet per second for 3 minutes which is 720 feet (4x60x3). Lastly 9 feet per second for 5 minutes which is 2,700 feet (9x60x5). Then you add up those three totals, 840 + 720 + 2,700 = 4,260. So the elevation is -4,260 feet, or 4,260 feet below sea level
