2-0.5=1.5
3.5-2=1.5
Therefore difference is 1.5=n
1.5n-1 is nth term
When n=20
=29
Hi there!

Find the total area by breaking the figure into two rectangles, one trapezoid, and one triangle.
Rectangles:
A = l × w
A = 2.75 × 4 = 11 in²
Solve for the other rectangle's length by subtracting from the total:
12 - 2 - 3 - 4 = 3
A = 3 × 3 = 9 in²
Total rectangle area: 11 + 9 = 20 in²
Trapezoid:
A = 1/2(b1 + b2)h
A = 1/2(4.25 + 2.75)3 = 21/2 = 10.5 in²
Triangle:
A = 1/2(bh)
A = 1/2(2.5 · 2) = 2.5 in²
Add up all of the areas:
20 + 10.5 + 2.5 = 33 in²
<span>lengths are in ratio 1:3
areas are in ratio
1 : 3</span>²<span> = 1: 9
area of ADG = 9 x 42 = 378 </span>