In triangle ABC, the length of side AB is 20 inches and the length of side BC is 28 inches. Which of the following could be the length of side AC? A. 50 inches B. 38 inches C. 53 inches D. 6 inches

B). 38:inches

Step-by-step explanation: the two length 20 and 28 have a close range of value. So the next close range of value is the 38 inch which will make a perfect fit.

Note this rule is by trial and error method and no formula is behind it.

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!