2+1/3n=8 is the answer, I believe.
Quick Answer SSS
Proof
AC = DB
AB = DC
BC = BC This side is equal to itself and is common to both triangles.
Three sides of one triangle equal to 3 sides of the other means that the triangles are congruent. It is the Theorem you need.
4(-9*x)
Multiply the two numbers
-36x
Final answer: -36x
You do 27 divided by 90 27/90=0.3 and then move the decimal two places which would give you 30%