Help anyone?? Struggling hard..

Give the equations of two different lines that are perpendicular to the line 3x + 4y = 7.

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

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?