Answer:
a. 
b. 
Step-by-step explanation:
change switch x and y and then solve for y.
a. 





same for b.
b. 





Answer:
Step-by-step explanation:
A diameter of the circle.
4/15 because you make it into a fraction: 8/30, you find the GCF which is 2, so then you divide both the numerator and denominator by 2 and get 4/15 at it's simplest term
Add 7 and 2 you will get 9, therefore the length of the post is 9.