1.2365
irrational or rational?

(40 points) i need some . an answer definition is appreciated as well.

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)

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?