C...to show this, interchange letters: x = (y+1)/(y-1)xy-x = y + 1xy - y) = x + 1y(x-1) = x+1y = (x+1)/(x-1) ⇐ this is f-1(x) and it's identical to f(x). Note: <span>the equal sign is missing in the definitions of the functions c. & d.</span>
Answer:
9 hours
Step-by-step explanation:
Set up the equations: x is the amount of hours Amber worked and y is the hours Jake worked
8x + 8y = 120
y = 3 + x
Substitute the second equation into the first
8x + 8(3+x) = 120
Distribute
8x + 24 + 8x = 120
Combine like-terms
16x + 24 = 120
Subtract 24 on both sides
16x = 96
Divide 16 on both sides
x = 6 (hours Amber worked)
Plug in this x-value into on of the two equations. I will use the second
y = 3 + 6
y = 9
