1. Ideal Mechanical Advantage (IMA): 9
Explanation:
For a wheel and axle system like the steering wheel, the IMA is given by:

where
is the radius of the wheel
is the radius of the axle
For the steering wheel of the problem, we see that
and
, so the IMA is

2. Efficiency: 88.9%
Explanation:
The efficiency of a system is defined as the ratio between the AMA (actual mechanical advantage) and the IMA:

In this problem, AMA=8 and IMA=9, so the efficiency is

Plug in the corresponding values into y = mx + b
8.18 in for y
1.31 in for m
17.2 in for b
8.18 = 1.31x + 17.2
Now bring 17.2 to the left side by subtracting 17.2 to both sides (what you do on one side you must do to the other). Since 17.2 is being added on the right side, subtraction (the opposite of addition) will cancel it out (make it zero) from the right side and bring it over to the left side.
8.18 - 17.2 = 1.31x
-9.02 = 1.31x
Then divide 1.31 to both sides to isolate x. Since 1.31 is being multiplied by x, division (the opposite of multiplication) will cancel 1.31 out (in this case it will make 1.31 one) from the right side and bring it over to the left side.
-9.02/1.31 = 1.31x/1.31
x ≈ -6.8855
x is roughly -6.89
Hope this helped!
~Just a girl in love with Shawn Mendes
Velocity is defined as a change in position.