1. Use the FOIL method (x+9)(x+9)
First, outer, inner, last

Add your like terms

2. When you add or subtract polynomials you add or subtract the like terms and then put them in order from largest to smallest exponents.
3.

4. Since it is the perimeter, we add the 3 together.

Add the like terms together:

Put them in order of exponents

Hope this helps
Whata re the answers that i can oick from
Answer:
her balance aka ADB would be 372.08
Answer:
The height is 4.472
Step-by-step explanation:
That formula is Heron's formula.
Where "s" is calculated like this:
s = (a + b + c) / 2
In this case:
a = 14
b = 12
c = 6
replacing:
s = (14 + 12 + 6) / 2
s = 16
Now we calculate the area:
A ^ 2 = 16 * (16−14) * (16−12) * (16−6)
A ^ 2 = 1280
A = 35.777
The area of the triangle is:
A = b * h / 2
In this case we will take the base as the longest side of the triangle, that is to say = 14
Thus:
h = A * 2 / b
h = 35.777 * 2/16
h = 4.472
So the height is 4.472
Answer: Linear pairs of angles add up to 180 degrees. A+B=180
Step-by-step explanation: A linear pair of angles is formed when two lines intersect. Two angles are said to be linear if they are adjacent angles formed by two intersecting lines. The measure of a straight angle is 180 degrees, so a linear pair of angles must add up to 180 degrees