Who ever answers this first will answer

hello from mrbilldoesmath!

answer:

x - 3

discussion:

x^2 - 9 = (x-3) (x+3)   so

(x^2-9)/ (x + 3) = x-3

you,

mrb

by definition, an arc subtended by a central angle of some given measure has the same measure. so .