All I need is a yes or no answer if these equations are true. Please help ASAP

Find the length of the following tangent segments to the circles centered at o and o' whose radii are 5 and 3 respectively and the distance between o and o' is 12. what is the tangent segment of cd?

Which expressions are equivalent to k/2 choose 2 answers: a k-2 b 2/k c 1/2k d k/2 e k+k

Solve the following inequalities and show the solution on a number line. 2x+3< 3(4x+5)