Respuesta :

Answer:

6 different isosceles triangles.

Step-by-step explanation:

This is a AMC 8 2005 question. (You can search up their solution)

There are 6 triangles:

6, 6, 11

7, 7, 9

8, 8, 7

9, 9, 5

10, 10, 3

11, 11, 1

There are only 6 because if there was an isosceles triangle with side lengths such as 5, 5, 13 the triangle would be impossible since the two smaller side lengths must sum up to be greater than the longest side length.

The number of isosceles triangles has integer side lengths and a perimeter of 23 is 6.

What is the isosceles triangle?

In an isosceles triangle, two sides and angles are equal. The sum of the angle of the triangle is 180 degrees.

Given

Isosceles triangles have integer side lengths and a perimeter of 23.

Let x be the isosceles side and y be the other side. Then

[tex]\rm 2x + y = 23[/tex] ...1

And we know that the sum of the two sides of the triangle must be greater than the third side. Then

[tex]\rm 2x >y[/tex] ...2

From equations 1 and 2, we have

x > 5.75

But the value of x is an integer then x will be 6. Then

All possibilities are

[tex]6 + 6 > 11\\\\7 + 7 > 9\\\\8+8>7\\\\9+9>5\\\\10+10>3\\\\11+11>1[/tex]

Thus, the number of isosceles triangles has integer side lengths and a perimeter of 23 is 6.

More about the Isosceles triangle link is given below.

https://brainly.com/question/7915845

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