Respuesta :

Given that the external angle formed by the two tangent is 40° and the

part of [tex]m \widehat{LMJ}[/tex] is 138°, we get that  [tex]m \widehat{MJ}[/tex] = 87°.

Which property can be used to find  [tex]m \widehat{MJ}[/tex] ?

Using the two tangent angle theorem, we have;

[tex]m \angle K = \mathbf{ \dfrac{1}{2} \times \left(\widehat{LMJ} - \widehat{LJ} \right)}[/tex]

m∠K = 40°

[tex]m \widehat{ML}[/tex] = 138°

[tex]m \widehat{LMJ}[/tex] = [tex]m \widehat{ML}[/tex] + [tex]m \widehat{MJ}[/tex]

[tex]m\widehat{LJ} = \mathbf{360^{\circ} - \left(m\widehat{ML} + m\widehat{MJ} \right)}[/tex]

Which gives;

[tex]m \angle K = \dfrac{1}{2} \times \left(\widehat{LMJ} - \left( 360^{\circ} - \left(m\widehat{ML} + m\widehat{MJ} \right) \right)\right)[/tex]

Therefore;

[tex]m\angle K= \dfrac{1}{2} \times \left(m \widehat{ML} + m \widehat{MJ} - \left( 360^{\circ} - \left(m\widehat{ML} + m\widehat{MJ} \right) \right)\right)[/tex]

[tex]40^{\circ}= \mathbf{ \dfrac{1}{2} \times \left(138^{\circ} + 2 \cdot m \widehat{MJ} - 232^{\circ} \right) \right)\right)}[/tex]

Which gives;

  • [tex]m \widehat{MJ}[/tex] = 87°

Learn more about two angle tangent theorem here:

https://brainly.com/question/10685817