William payed $8.55 at the discount price
Answer:
c. f(x) x+1/x-1
Step-by-step explanation:
To answer this question, we need to check each answer one by one until we find the right one.
y = (x+6)/(x-6)
switch x and y
x = (y+6)/(y-6)
solve for y
x(y-6) = y+6
xy - 6x = y+6
y(x-1) = 6x+6
y = (6x+6) /(x-1) = 6(x+1)/(x-1)
f^-1(x) = 6(x+1)/(x-1)
y = (x+2)/(x-2)
switch x and y
x = (y+2)/(y-2)
solve for y
x(y-2) = y+2
xy -2x = y+2
y(x-1) = 2x+2
y = (2x+2)/(x-1)
f^-1(x) = 2(x+1)/(x-1)
y = (x+1)/(x-1) ------ correct one
switch x and y
x = (y+1)/(y-1)
solve for y
x(y-1) = y+1
xy - x = y+1
y(x-1) = x+1
y = (x+1)/(x-1)
f^-1(x) = (x+1)/(x-1)
f(x) = f^-1(x)
100-15=85
Therefore 0.85 is the multiplier
So 243.00 times by 0.85 = 206.55
The answer is C.) 33% i believe. Excuse me if i'm wrong!!!!!
Answer:
x=-1, y=1. (-1, 1).
Step-by-step explanation:
5y-6=x
y=-x
-----------
5(-x)-6=x
-5x-6=x
-5x-x=6
-6x=6
x=6/-6
x=-1
y=-(-1)=1