A line parallel to a triangle's side splits AB into lengths of x - 6 and x. The other side, AC, is split into lengths of x + 6 and x + 20. What is the length of AC? A) 36 B) 46 C) 56 D) 66

Respuesta :

Option C: 56 is the length of AC

Explanation:

Let DE be the line parallel to BC

Let D divides the side AB and E divides the side E

The lengths of the sides are [tex]AD=x-6[/tex] , [tex]DB=x[/tex], [tex]AE=x+6[/tex] and [tex]EC=x+20[/tex]

We need to determine the length of AC

The value of x:

By side splitter theorem, we have,

[tex]\frac{AD}{DB}=\frac{AE}{EC}[/tex]

Substituting the values, we have,

[tex]\frac{x+6}{x}=\frac{x+6}{x+20}[/tex]

Simplifying, we get,

       [tex](x+6)(x+20)=x(x+6)[/tex]

[tex]x^2+20x-6x-120=x^2+6x[/tex]

       [tex]x^2+14x-120=x^2+6x[/tex]

               [tex]14x-120=6x[/tex]

                          [tex]8x=120[/tex]

                            [tex]x=15[/tex]

Thus, the value of x is 15

Length of AC:

The length of AC is given by

[tex]AC=AE+EC[/tex]

[tex]AC=x+6+x+20[/tex]

[tex]AC=15+6+15+20[/tex]

[tex]AC=56[/tex]

Thus, the length of AC is 56

Hence, Option C is the correct answer.