Rita needs to memorize words on a vocabulary list for Russian class. She has memorized 18 of the words, which is one-third of the list. How many words are on the list?

6

Step-by-step explanation:

3333333333333333333333333333333333333333333333

step-by-step explanation:

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2