Respuesta :

Answer:

The converse of the Pythagorean Theorem, [tex]{\bf (PQ)}^{\bf 2}={\bf a^2+b^2}[/tex] is true

Step-by-step explanation:

The Pythagorean theorem or Pythagoras's theorem is a statement about the sides of a right triangle.

If the lengths of the legs are a and b, and the length of the hypotenuse is c, then, [tex]a^{2}+b^{2}=c^{2}[/tex]

To prove that the converse of the Pythagorean Theorem, [tex](PQ)^2=a^2+b^2[/tex]

By the Pythagorean Theorem, [tex](PQ)^2=a^2+b^2[/tex]

But we know that [tex]a^2+b^2=c^2[/tex] and  [tex]c=AB[/tex]

So,  [tex](PQ)^2=a^2+b^2=(AB)^2[/tex]

That is, [tex](PQ)^2=(AB)^2[/tex]

Since PQ and AB are lengths of sides, we can take positive square roots.

PQ=AB

That is, all the three sides of [tex]\triangle PQR[/tex] are congruent to the three sides of [tex]\triangle ABC[/tex] . So, the two triangles are congruent by the Side-Side-Side Congruence Property.

Since [tex]\triangle ABC[/tex] is congruent to [tex]\triangle PQR[/tex] and [tex]\triangle PQR[/tex] is a right triangle, [tex]\triangle ABC[/tex] must also be a right triangle.

This is a contradiction. Therefore, our assumption must be wrong.

Therefore the converse of the Pythagorean Theorem,

[tex](PQ)^2=a^2+b^2[/tex]

If a^2 + b^2 = c^2, then the triangle is a right triangle.