Ignore that there's an answer I accidently clicked it

Which of the following transformations does not preserve congruence? * 5 points a. (x, y) → (y − 3, x − 3) b. (x, y) → (x + 5, y − 1) c. (x, y) → (y + 9, −x + 2) d. (x, y) → (3x + 1, 3y − 2)

Remmi wrote the equation of the line y=⅓(x+2) he solved for x and got x=3y-2 which of the following is an equivalent equation for x? a.x=y-11/3 b.x=y+7/3 c.x=3(y-⅔) d.x=3(y+⅔)

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?