No its not a prime number its actually a square number.
4 pages Elena = 5 pages Jada
To figure out how many pages Jada reads if Elena reads 1, divide 5 by 4: 1.25. This means that for every 1 page Elena reads, Jada reads 1.25 pages.
So if Elena reads 9 pages, multiply 1.25 by 9: 11.25 pages that Jada reads.
For S pages read by Elena, this is a variable, so I’m assuming it means for every S pages, Jada reads 1.25S
interior angle of a regular 18-gon.
It is easier to calculate the exterior angle of a regular polygon of n-sides (n-gon) by the relation
exterior angle = 360/n
For a 18-gon, n=18, so exterior angle = 360/18=20 °
The value of each interior angle is therefore the supplement, or
Interior angle = 180-20=160 degrees.
Naming of a 9-gon
A polygon with 9 vertices is called a nonagon (in English) or enneagon (French ennéagone, but the English version is sometimes used)
You had a good start with the correct answer.
Exterior angle of a 15-gon
The exterior angle of a 15-gon can be calculated using the relation given in the first paragraph, namely
Exterior angle = 360/15=24 degrees
I can’t see good this image
F(x) = 112 - kx
f(-3) = 121
f(-3) = 112 - k(-3)
f(-3) = 112 + 3k
121 = 112 + 3k
121 - 112 = 3k
9 = 3k
9/3 = k
3 = k <===