Solve the following for the x and y values. x being 0 when solving for y, and vice versa.
question 1: x + y = 4

question 2: x - y = -3

Three coins are flipped. what is the probability that there will be at least two tails?

What is the length of the unknown leg in the right triangle ?

Marco is studying a type of mold that grows at a fast rate. he created the function f(x) = 345(1.30)x to model the number of mold spores per week. what does the 1.30 represent? how many mold spores are there after 4 weeks? round your answer to the nearest whole number. 1.30 represents the number of mold spores marco had at the beginning of the study; 985 mold spores 1.30 represents the number of mold spores grown in a given week; 448 mold spores 1.30 represents the 30% rate of weekly growth; 345 mold spores 1.30 represents the 30% rate of weekly growth; 985 mold spores