A toxin increases from 12ppm to 48 ppm. What percent increase is this?

Choose the point slope form of the equation below that represents the like that passes through the points (-6,4) and (2, 0)

Dexter read 11 science fiction books and 5 history books. lena read 9 science fiction books and 4 history books. compare the students’ ratios of science fiction books to history books. 1. determine the ratios’ form:    science fiction books to history books 2. write the ratios as fractions:    dexter: 115; lena: 94 3. rewrite with a common denominator. 4. compare. 5. answer the question. determine which shows the correct comparison of the ratios for this problem.

What is the result of adding the system of equations? 2x+y=4 3x-y=6