Which of these is a trinomial? a.2x^3 – 7y^3 + 14 b.5xy c.2y^2 + 7y d.2x – 7

I don't really know, but if not just look up a trinomial calculator and it will tell you .

Hope this helps :) 

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet