Answer:
Step-by-step explanation:
As we know that
- The exterior angle of a triangle is the result of the sum of the measures of the two non-adjacent interior angles.
In other words,
- An exterior angle is equal to the sum of the two angles not right next to it.
so from the diagram,
- (11x+5) is the exterior angle
- 30° and (-5+7x) are the two non-adjacent interior angles.
so
[tex]11x+5\:=\:30+\:\left(-5+7x\right)[/tex]
[tex]11x+5=30-5+7x[/tex]
[tex]11x=7x+20[/tex]
subtract 7 from both sides
[tex]11x-7x=7x+20-7x[/tex]
[tex]4x=20[/tex]
Divide both sides by 4
[tex]\frac{4x}{4}=\frac{20}{4}[/tex]
[tex]x=5[/tex]
Therefore, x = 5
