Which is equivalent to (9y2 – 4x)(9y2 + 4x), and what type of special product is it?
81y4 – 16x2, a perfect square trinomial
81y4 – 16x2, the difference of squares
81y4 – 72xy2 – 16x2, a perfect square trinomial
81y4 – 72xy2 – 16x216, the difference of squares

Last one and the bottom answer choice is y=(x-4)^2+1 you guys!

*let m∠cob = 50°30’, m∠aob = 70° and m∠aoc = 20°30’. could point c be in the interior of ∠aob? why? a. point c could be the interior of aob but it is not the only case b. point c is the interior of aob c. point c is not the interior of aob d. the given is not possible for the plane geometry answer

If the tip varies directly with the number of guest which equation represents between the tip,t, and the number of guest,g?