Question

In ΔLMN, \overline{LN}

Answer 1

Answer:

$\bold{\angle NLM = 10^\circ}$

Step-by-step explanation:

Given a ΔLMN.

Line LN is extended to point O.

such that:

$\text{m}\angle MNO = (5x-13)^{\circ}$

$\text{m}\angle NLM = (x-4)^{\circ}$ and

$\text{m}\angle LMN = (2x+19)^{\circ}$

To find:

$\text{m}\angle NLM=?$

Solution:

Kindly refer to the attached image for the given triangle and dimensions of angles.

Let us recall the external angle property of a triangle:

The external angle of a triangle is equal to the sum of two opposite internal angles.

i.e.

$\angle MNO = \angle NLM + \angle LMN\\\Rightarrow 5x-13 = x-4+2x+19\\\Rightarrow 5x-13 = 3x+15\\\Rightarrow 5x-3x = 13+15\\\Rightarrow 2x=28\\\Rightarrow x =14$

Putting the value of $x$ in $\angle NLM$.

$\angle NLM=14-4 \\\Rightarrow \bold{\angle NLM = 10^\circ}$