Answer:
Option B. 
Step-by-step explanation:
we know that
The area of a triangle is equal to

we have


Convert mixed numbers to an improper fractions


substitute the values

a. 40 if you dont believe me just look at a 40 degree triangle then the pic
The difference between two numbers are
and numbers are
and
so the equation is 
How to find the equation and what is the equation ?
equation, statement of equality between two expressions consisting of variables and/or numbers. In essence, equations are questions, and the development of mathematics has been driven by attempts to find answers to those questions in a systematic way.
if the difference of two numbers are 
And one number is
and another is 
So we write the equation with operation of subtraction

Learn more about the equations here :
brainly.com/question/28048736
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