\begin{aligned} 71{,}830=& 7 \text{ ten thousands} +1 \text{ thousand} + 8 \text{ hundreds} + 3 \text{ tens} 71{,}830=& 6 \text{ ten thousands} +\bigstar\text{ thousands} + 8 \text{ hundreds} + 3 \text{ tens} \end{aligned} 71,830=
71,830=


7 ten thousands+1 thousand+8 hundreds+3 tens
6 ten thousands+★ thousands+8 hundreds+3 tens

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

good job you smart son of a gun you are smarter that einstein. 7

nada

step-by-step explanation: