We have to prove that the tangent is an odd function.
If the tangent is an odd function, the following condition should be satisfied:

From the figure we can see that the tangent can be expressed as:
We can start then from tan(t) and will try to arrive to -tan(-t):

We have arrived to the condition for odd functions, so we have just proved that the tangent function is an odd function.
Answer:
the largest angle of the field is 149⁰
Step-by-step explanation:
Given;
perimeter of the triangular filed, P = 120 m
length of two known sides, a and b = 21 m and 40 m respectively
The length of the third side is calculated as follows;
a + b + c = P
21 m + 40 m + c = 120 m
61 m + c = 120 m
c = 120 m - 61 m
c = 59 m
B
↓ ↓
↓ ↓
↓ ↓
A → → → → → → → → → → → C
Consider ABC as the triangular field;
Angle A is calculated by applying cosine rule;

Angle B is calculated as follows;

Angle C is calculated as follows;

Therefore, the largest angle of the field is 149⁰.
Answer:
One piece of fabric: 10 x 6, or 60.
If one triangle is 15, she can cut 4 triangles from each piece of fabric.
If she has 24 pieces of fabric, she can cut 4 x 24, or 96 triangle patches.
Let me know if this helps!
Answer:
The first one is a the second one is b
Step-by-step explanation: