For the first picture using Pythagorean Theorem, we know that a^2 + b ^2 = c^2 but since we only know c ( 99.2) and b ( 62 ) we need to use the theorem to find a the equation we use for that is :
A = square root of ( c^2 - B^2 )
A = 77.44
Only 25 and 28 are functions.
A function must have only one y value per x value. For 26, the y value of 0 and multiple others have two different y values. For 27, all x values less than 0 have multiple y values.
Since the sequence is geometric, there is some constant

such that the sequence is recursively given by

By this definition, you can recursively substitute into the right hand side the definition for

to find an explicit formula for the

th term.

You know the second term, which means you can find

:

So, the 7th term of the sequence is
First, change the fractions to a common denominator, which is 21.
so 3/7 * 3/3 = 9/21
1/3 * 7/7 = 7/21
Add the two together
9/21 + 7/21 = 16/21
Then take 21/21 - 16/21 = 5/21
There is 5/21 of the pizza left.
3/4 times 16/9 is equal to 1 1/3.