If you look along the downward sloping line you can see that:
85+2x+x-10=180 combine like terms on left side
3x+75=180 subtract 75 from both sides
3x=105 divide both sides by 3
x=35
Now if L and M are parallel, angle 3 must be equal to x-10 because they are vertical angles (equal opposing angles). We know now that x=35 so:
angle 3 =35-10=25°
"An angle that forms a linear pair with one of the interior angle the triangle" is the best definition of an exterior angle of a triangle.
<u>Option: C</u>
<u>Explanation:</u>
When to the sum of the inward angles opposite outer angle of a triangle the sum of the inward angles opposite is equivalent thus understood as exterior angle of a triangle.
The Triangle outer angle theorem for more about is if at each vertex the equivalent angle is drawn, the outer angles always add up to 360°. In reality, this is valid for any convex polygon, not just triangles.
In the most easiest pattern , since any angle of triangle equivalent is 60′, the outer angle would be 120′. Therefore all exterior angles sum is:
120 + 120 + 120 = 360°.
Answer:
B = 70
Step-by-step explanation:
The sum of the angles of a triangle add to 180 degrees
A + B + C = 180
40 + 2x-30 + x+20 = 180
Combine like terms
3x + 30 = 180
Subtract 30 from each side
3x+30-30 = 180-30
3x = 150
Divide by 3
3x/3 =150/3
x = 50
We want to find angle B
B = 2x-30
=2(50) - 30
= 100 - 30
= 70
6(4x+5)=3(x+8)+3
24x+30 = 3x+24+3
24x-3x = 24+3-30
21x = -3
x = -3/21 = -0,14