Help me please, I’m having a quiz!!

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’s the nearest hundredth of 1.5757

1.)solve for z. -52=-4z 2.)solve for p 9/2.3=9.2 3.)solve for y. -1.17y=5.85 4.)solve for x. 3x/8=6