Question

20 points and brainliest!!!!

Answer 1

Answer:

C. 120º

Step-by-step explanation:

so we know that the inside of a triangle is 180º and since all the measures are the same we can do 180/3 to find how much each angle is.

180/3 = 60º

now we also know that a straight line is equal to 180º and since we already have one angle, all we have to do is subtract 60 from 180.

180 - 60 = 120º

Answer 2

Answer:

Answer:all the interior angles measures 60°

Answer:all the interior angles measures 60°and exterior angle is 120°

Step-by-step explanation:

all angles of equilateral triangle are equal, so

let them be x

• x+x+x = 180°
• ( sum of interior angles of triangle )
• 3x = 180°
• x = 180° / 3
• x = 60°

now x = interior angle = 60°

let the exterior angle be y

interior angle + exterior angle = 180°

( by linear pair )

• 60° + y = 180°
• y = 180° - 60°
• y = 120°

hence all exterior angles of an equilateral triangle measures 120°