Plzzz someone help me

Find the value of x. give reasons to justify your solutions! l, m ∈ kn

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?

What is the area of a triangle with a base of 7x and height of 8x expressed as a monomial? question 5 options: 1x 15x2 28x2 56x2