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The converse of the Pythagorean Theorem states that if the three sides of a triangle work for the equation a2 + b2 = c2, then the triangle is a right triangle. To prove this, you can use what’s called a proof by contradiction. That is, you can prove something is true because it cannot be false.Start by assuming a triangle is not a right triangle and the sides work for the equation a2 + b2 = c2. Here is a diagram of the triangle. Keep this diagram window open as you work on the tasks in this section.Now, create a right triangle with legs a and b. Call the hypotenuse n.Part A - Since triangle 2 is a right triangle, write an equation applying the Pythagorean Theorem to the triangle.Part BSince the equations for both triangles have a2 + b2, you can think of the two equations for c2 and n2 as a system of equations. Substitute what a2 + b2 equals in the first equation for a2 + b2 in the second equation. After you substitute, what equation do you get?Part CNow, take the square root of both sides of the equation from part B and write the resulting equation.Part DIs there any way for this equation to be true? How?Part EWhat does this show about the relationship between the two triangles?

The converse of the Pythagorean Theorem states that if the three sides of a triangle-example-1
User Mark Lalor
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14 votes

Answer and Explanation:

Given:

Part A: The equation for Triangle 2 is;


n^2=a^2+b^2

Part B: Since;


\begin{gathered} a^2+b^2=c^2,\text{ and } \\ n^2=a^2+b^2 \\ Therefore, \\ c^2=n^2 \end{gathered}

The resulting equation is c^2 = n^2

Part C: Let's take the square root of both sides from Part B;


\begin{gathered} √(c^2)=√(n^2) \\ c=n \end{gathered}

The resulting equation is c = n

Part D:

By taking the square root in Part B we can see that side c and side n are equal in triangle 1 and triangle 2 respectively. So the equation is true.

Part E:

The relationship, c = n, shows that triangle 1 is also a right triangle because we have that side c is equal to the hypotenuse side n of the right triangle 2.

The converse of the Pythagorean Theorem states that if the three sides of a triangle-example-1
User Go Dan
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