The number of items is modeled by h(x) = 0.42x^2 + 0.3x + 4, and the cost per item is modeled by r(x) = −0.005x^2 − 0.2x + 7. The total cost is the product of the number of items and the cost per item. Identify a polynomial q(x) that can be used to model the total cost.

John can eat 10 cookies in 1/2 hr how many cookies can he eat in 45 minutes make a proportion and solve

What is the value of x in the equation 2(x-4) = 4(2x + 1)?

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?