Inserting all the given information into the identity, we have

Answer:
This is done by stating descriptions of these terms.
Step-by-step explanation:
Undefinable terms are terms with no formal definitions. Formal definitions are obtained when specific words are used to define a term. In mathematics, specifically, Geometry words like line, point, and plane have no definite definition, So descriptions are used to identify them.
For example, in describing a point, we note that a point has no dimensions, it is usually denoted with a capital letter, and it indicates a position. Also in a coordinate plane, it is denoted with descriptions such as (u,v). Corresponding descriptions are given of other undefinable terms.
Answer: The area common to both triangle is 31.77 sq. cm.
Step-by-step explanation:
Since we have given that
30-60-90 triangles are placed.
So, the ratio of sides would be

Since Hypotenuse = 12 cm
So, it becomes,

So, Base would be

and Perpendicular would be

So, Area common to the both triangles would be

Hence, the area common to both triangle is 31.77 sq. cm.
Answer:
E + F = 2c^2 + 5c + 4
Step-by-step explanation:
E=6c^2-2c-1
F=-4c^2+7c+5
E+F= 6c^2 -2c -1 + -4c^2 + 7c + 5
E + F = 6c^2 - 4c^2 - 2c + 7c - 1 + 5
E + F = 2c^2 + 5c + 4