The total cost of four pens and seven mechanical pencils is $12.27. the cost of each pencil is 25 cents a. using an arithmetic approach, find the cost of the pen

If sec theta = 5/3 and the terminal point determined by theta is in quadrant 4, then

How can you tell when x and y are not directly proportional?

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?