The answer is A because you have to use the process of substitution
<h2>Hello There today we will solve your problem</h2>
<em>Response-</em>
<em>ABC is absolutely a right triangle</em>
<em>we can use the pythagorean theorem to solve this</em>
<h3><em>Definitions</em></h3>
Right Triangle - <em>A right triangle or right-angled triangle, or more formally an orthogonal triangle, is a triangle in which one angle is a right angle. The relation between the sides and other angles of the right triangle is the basis for trigonometry. The side opposite to the right angle is called the hypotenuse.</em>
Pythagorean Theorem - <em>In mathematics, the Pythagorean theorem, or Pythagoras' theorem, is a fundamental relation in Euclidean geometry among the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse is equal to the sum of the areas of the squares on the other two sides.</em>
<em>_________________</em>
<em>To use to the Pythagorean Theorem it is</em>

For our equation
would be
would be 
<em>_________________</em>
<h2><em>Solve</em></h2>

Since we got
this is a right triangle since it's what we had before.
Answer:
final answer is 6
Step-by-step explanation:
Given 
To find the difference quotient use formula



Now plug it in the formula




6