1 base. The triangular pyramid has 1 base, and that is the square at the bottom. Hope this helps.
Inverse proportion is of the form:
y=k/x, in this case the variables are
z=k/x, and we are given the point (6,2) so we can solve for k
2=k/6
12=k, so our equation is:
z=12/x, so when x=13
z=12/13
Answer: (3x + 11y)^2
Demonstration:
The polynomial is a perfect square trinomial, because:
1) √ [9x^2] = 3x
2) √121y^2] = 11y
3) 66xy = 2 *(3x)(11y)
Then it is factored as a square binomial, being the factored expression:
[ 3x + 11y]^2
Now you can verify working backwar, i.e expanding the parenthesis.
Remember that the expansion of a square binomial is:
- square of the first term => (3x)^2 = 9x^2
- double product of first term times second term =>2 (3x)(11y) = 66xy
- square of the second term => (11y)^2 = 121y^2
=> [3x + 11y]^2 = 9x^2 + 66xy + 121y^2, which is the original polynomial.