National Bank advertises an intrest rate (in decimal form) of 0.12 if your initial investment is 500 and you want to acumalte $900 in intrest, how many years do you need to invest

It will take 15 years for $500 to yield $900 at an interest rate of 0.12

Step-by-step explanation:

Simple Interest equals Principal times Rate times The time in years,

That is SI = P*R*T

SI is $900

P = $500

R = 0.12

T i.e. Time is unknown

T will be equal to SI divided by P*R

i.e., T = SI/PR

T = $900/$500*0.12 = 900/60

T = 15 years.

Therefore, it will take $500 investment to yield $900 interest in 15 years at an interest rate of 0.12

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