How do you find the circumference of a circle?

Xto the second power plus 14x plus 48. what are the factors? we are doing factoring trinomials with a=1

Which expression is equivalent to the expression shown?

In a right triangle δabc, the length of leg ac = 5 ft and the hypotenuse ab = 13 ft. find: b the length of the angle bisector of angle ∠a.