is this quadrilateral a parallelogram?If yes, state the definition or theorem that justifies your answer.​

is this part of a question or something

b. x + 1

step-by-step explanation:

i'am smart

first, you divide the triangle in two, tô form a retangle triangle. after, using pythagoream theorem:

18^2 = 14^2 + (x/2)^2

(x^2/4) + 196 = 324

x^2/4 = 324 - 196

x^2/4 = 128

x^2 = 512

x = √512

x = √2^9

x = 16√2 cm

i hope i you.

the answer to your question is c.)   volcanoes built the mountains and earthquakes tore them down.

step-by-step explanation: