You a miguel cervantes de navas y colon, captain in the royal spanish army in seville in the year 1842. outside your barracks window is a stack of cannonballs, as shown in the illustration. on an idle afternoon you decide to calculate the number of cannonballs in the stack. what is the number of cannonballs.

650 cannonballs

A

Step-by-step explanation:

The stack of Cannonballs is really the sum of squares.

The top layer is 1^2

The second layer is 2^2

The Third layer is 3^2

layer 12 ( the bottom layer) is 12^2

The formula for this is

n*(n + 1)*(2n + 1)/6

n = 12

12(12 + 1)(2*12 + 1)/6

12 * 13 * 25/6

650

The sum of this pyramid is 650 Cannonballs

d i think

step-by-step explanation:

step-by-step explanation:

this can be solved first with pythagorean theorem, which tells us to square both legs of the triangle and sum it. this will be equal to the square of the hypotenuse.

the hypotenuse is the side "opposite" the 90 degree angle, which is x.

so we can write using pythagorean theorem,

simplifying:

to further simplify this radical, we need to use the property  

thus