The expression for for the sum of k and 8 would be k+8
The actual answer is 28,350
$1.60.
You do 100 divided by 625 to get 16 cents. You then multiply .16 times 10 to get $1.60
The apothem is the distance from the center to the midpoint of one of the sides of a regular polygon. You can make a right triangle with the apothem, the line from the midpoint to the corner and the line from the center to the corner. An equilateral triangle has 60 degree angles (180/3). The right triangle has half of one of those angles so 30 degrees. Now we have a 30-60-90 triangle where the short leg is 5cm. The long leg, which is also half of one side of the triangle is thus

. A whole side of the triangle is

. Multiply that by 3 to get the perimeter of <span>

.</span>