Respuesta :

sqdancefan

Answer:

  ∠a = 39°

  ∠b = 129°

Step-by-step explanation:

Vertical angles are congruent. An exterior angle of a triangle is equal to the sum of the remote interior angles.

Application

Angle y and angle 'a' are vertical angles, so congruent.

  ∠a = ∠y = 39°

The angle marked 'b' is an exterior angle to the triangle. Its remote interior angles are 'a' and the one marked 90°.

  ∠b = ∠a +90° = 39° +90°

  ∠b = 129°

Kailes

[tex] \huge\mathbb{ \underline{SOLUTION :}}[/tex]

Given:

  • [tex]\longrightarrow\bold{m<a= \: 39}[/tex] ✓

  • [tex]\longrightarrow\bold{m<b= \: 141}[/tex]

In the given figure, angles a and y are vertically opposite angles. The measure of vertical angles is equal, therefore :-

[tex]\small\longrightarrow\sf{m<a = m<y}[/tex]

[tex]\small\longrightarrow\sf{m<a= \: 39^\circ}[/tex]

Next, angles a and 90° are the opposite interior angles to the exterior angle b. By the triangle theorem below :-

[tex]\small\longrightarrow\sf{m<b=m<a+90^\circ}[/tex]

[tex]\small\longrightarrow\sf{39^\circ+90^\circ}[/tex]

• [tex]\small\longrightarrow\sf{m<b= 129^\circ}[/tex]

[tex]\huge \mathbb{ \underline{ANSWER:}}[/tex]

m<a= [tex]\large\sf{\boxed{\sf 39^\circ}}[/tex]

m<b = [tex]\large\sf{\boxed{\sf 129^\circ}}[/tex]