Answer:
Step-by-step explanation:
Ellie:; 105/3 = 35 wpm
Vivian: 120/4 = 30 wpm
In this problem, we need to plug in the given x values for

and find a and b.
When we plug in 1, we get:

Simplify:



We got our first statement about the values of the variables. If we find one more we can find those 2 variables.
We have another given root: 4.
Plug it in:




Now we have our second one. We can combine them:

I use elimination method which is easier here.
Multiply the top equation by -1:

Add them up:

Simplify:

Now we have a, we can plug in one of those equations to find b:



So, the answers are

and

.
The rule for dilation (scale factor k) about the origin is given by:
(x,y)->(kx,ky)
The scale factor k can be obtained from any one of the ratios:
Arc length has a formula that is similar to arc measure, but arc length is expressed in inches or meters or miles, etc., whereas measure is expressed in degrees, like an angle. The formula for each take this into account. Since the arc length is part of the length of the outside of the circle, the formula includes the circumference for a circle.

, where theta is the degree measure of the central angle intersecting the arc you're looking for, and d is the diameter of the circle. Our formula would look like this with the info we have:

which can be simplified to

which can be simplified even further to

. And that's your answer!