6. Isosceles triangle JKL has a perimeter of 32 units
and the given vertices J(-3,-9), K(-3,6), and
L(x,-1.5)
What is a possible x-coordinate for point L?

Respuesta :

Answer:

The x coordinate will be 8.5

The perimeter of the triangle is the sum of its side lengths

The possible x-coordinates of point L are -7 and 1

The vertices of the triangle are given as:

[tex]\mathbf{J = (-3,-9)}[/tex]

[tex]\mathbf{K = (-3,6)}[/tex]

[tex]\mathbf{L = (x,-1.5)}[/tex]

Start by calculating distances JK, JL and KL using the following distance formula

[tex]\mathbf{d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}}[/tex]

So, we have:

[tex]\mathbf{JK = \sqrt{(-3 - -3)^2 + (-9 - 6)^2}}[/tex]

[tex]\mathbf{JK = \sqrt{0 + 225}}[/tex]

[tex]\mathbf{JK = \sqrt{225}}[/tex]

[tex]\mathbf{JK = 15}[/tex]

[tex]\mathbf{JL = \sqrt{(-3 - x)^2 + (-9 - -1.5)^2}}[/tex]

[tex]\mathbf{JL = \sqrt{(-3 - x)^2 + 56.25}}[/tex]

[tex]\mathbf{KL = \sqrt{(-3 - x)^2 + (6 -- 1.5)^2}}[/tex]

[tex]\mathbf{KL = \sqrt{(-3 - x)^2 + 56.25}}[/tex]

The triangle is said to be an isosceles triangle.

By comparison:

[tex]\mathbf{JL = KL}[/tex]

The perimeter is represented as:

[tex]\mathbf{P = JK + JL + KL}[/tex]

Substitute 32 for P

[tex]\mathbf{JK + JL + KL = 32}[/tex]

Substitute 15 for JK

[tex]\mathbf{15 + JL + KL = 32}[/tex]

Subtract 15 from both sides

[tex]\mathbf{JL + KL = 17}[/tex]

Substitute JL for KL

[tex]\mathbf{JL + JL = 17}[/tex]

[tex]\mathbf{2JL = 17}[/tex]

Divide both sides by 2

[tex]\mathbf{JL = 8.5}[/tex]

Recall that:

[tex]\mathbf{JL = \sqrt{(-3 - x)^2 + 56.25}}[/tex]

Substitute 8.5 for JL

[tex]\mathbf{8.5 = \sqrt{(-3 - x)^2 + 56.25}}[/tex]

Square both sides

[tex]\mathbf{72.25 = (-3 - x)^2 + 56.25}[/tex]

Subtract 56.25 from both sides

[tex]\mathbf{16 = (-3 - x)^2 }[/tex]

Take square roots of both sides

[tex]\mathbf{\pm 4 = -3 - x}[/tex]

Add 3 to both sides

[tex]\mathbf{ 3\pm 4 = - x}[/tex]

Rewrite as:

[tex]\mathbf{ -x = 3\pm 4 }[/tex]

Multiply both sides by -1

[tex]\mathbf{ x = -3\pm 4 }[/tex]

Split

[tex]\mathbf{ x = (-3- 4),(-3+4) }[/tex]

Solve

[tex]\mathbf{ x = (-7),(1) }[/tex]

Hence, the possible x-coordinates of point L are -7 and 1

Read more about coordinates at:

https://brainly.com/question/10364988