4x+4y=-20 and - 3x-12y=-60

Sarah works at a concession stand for 2 hours show earn $15.50 but if she works for 4 hours she learned $31 find the rate of change?

What does 25-15 equal?

A boat costs 16,000 and decreases in value by 14% per year. How much will the boat be worth after 11 years?

2x-h=x+a (Solve for x) (Where exactly do I start and how do I solve for x?)

The daily exchange rates for the five-year period 2003 to 2008 between currency A and currency B are well modeled by a normal distribution with mean 1.094 in currency A (to currency B) and standard deviation 0.013 in currency A.

What is the domain of f (x) = cos (x) ?

Mike and Kim invest $14,000 in equipment to print yearbooks for schools. Each yearbook costs $7 to print and sells for $35. How many yearbooks must they sell before their business breaks even?

What is the solution to the system of equations? Use the substitution method. j + k = 3 j - k = 7 A. The solution is (8, 1) B. The solution is (5, - 2) C. There is no solution. D. There are an infinite number of solutions.

30% of what number is 10.2

Long division 19 divide 23.94