Answer:
(a)The missing measurements are 9 feet and
.
(b)Therefore, the length of the fence is 
Step-by-step explanation:
The diagram of the yard is attached below.
(a)I have labeled the missing dimensions of the yard as x and y.
Therefore:

Similarly:

The missing measurements are 9 feet and
.
(b)Length of the Fence
The fence is rectangular shaped with:
Length = 
Width = 
Perimeter of a Rectangle = 2(L+W)
Therefore, the length of the fence

Answer:
1. x^4 -x^3 -4x^2 -3
a1 = -7.4
an = an-1 -13.8 (choice 1)
Step-by-step explanation:
f(x) = x^4 -x^2 +9
g(x) = x^3 +3x^2 +12
We are subtracting
f(x) -g(x) =x^4 -x^2 +9 - ( x^3 +3x^2 +12)
Distribute the minus sign
x^4 -x^2 +9 - x^3 -3x^2 -12
I like to line them up vertically
x^4 -x^2 +9
- x^3 -3x^2 -12
-------------------------
x^4 -x^3 -4x^2 -3
2. a1 = -7.4
To find the common difference, take term 2 and subtract term 1
-21.2 - (-7.4)
-21.2 + 7.4
-13.8
an = an-1 -13.8
I'm sorry, but I don't understand ;-;
im assuming i just pick two angles cause i cant see the options? two 90 degree angles.
and my name is teagan too :D