Suppose that a and b are integers, a ≡ 4 (mod 13), and b ≡ 9 (mod 13). find the integer c with 0 ≤ c ≤ 12 such that a. c ≡ 9a (mod 13). b. c ≡ 11b (mod 13). c. c ≡ a + b (mod 13). d. c ≡ 2a + 3b (mod 13). e. c ≡ a2 + b2 (mod 13). f ) c ≡ a3 − b3 (mod 13)

Helena lost her marbles. but then she found them and put them in 44 bags with mm marbles in each bag. she had 33 marbles left over that didn't fit in the bags.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

An equation in slope-intersept form the lines that passes thought (-8,1) and is perpindicular to the y=2x-17.