A triangle is made of letter A
Answer: If
and
, then 
Step-by-step explanation:
Let be "a", "b", and "c" all real numbers, the Transitive property of equalities states that :
If
and
, then 
You can observe that if two numbers are equal to the same number, then all this numbers are equal to each other.
For example, applying the Transitive property of equalities to:
and 
You can equate them:

And solve for "x":

You do both of those multiplied by each other