81
(-9)(-9) is 81
Multiplying two negatives gives a positive
<h3>Solving for the measurements of Complementary Angles</h3><h3>
Answer:</h3>
and 
<h3>
Step-by-step explanation:</h3>
Recall that Angles that are complementary to each other add up to
.
Let
be the measure of the complementary angle.
If an angle is
more than its complementary angle, the measure of that angle is
. The sum of both angles are expressed
but since the have to add to
as they are complementary,
.
Solving for
:

Since the other angle measures
, we can plug in the value of
to find the measure of the angle.
Evaluating
:

The measure of the angles are
and 
As scientists conduct their research, they make observations and collect data. The observations and data often lead them to ask why something is the way it is. Scientists pursue answers to these questions in order to continue with their research.
Answer:

Step-by-step explanation:
we know that
The surface area of a rectangular prism is equal to the area of its six rectangular faces
using the net
The surface area is equal to
![SA=2[(16)(6)]+2[(16)(8)]+2[(8)(6)]](https://tex.z-dn.net/?f=SA%3D2%5B%2816%29%286%29%5D%2B2%5B%2816%29%288%29%5D%2B2%5B%288%29%286%29%5D)

