Question

Find the measure of angle x in the figure below:

45°
80°
55°
100°

Answer 1

what's the value of angle "y"?

Answer 2

55

Answer 3

notice, "x" and "y" are both 'vertical angles"
and vertical angles... well -> http://www.mathsisfun.com/geometry/vertical-angles.html

Answer 4

the angles in a triangle all add up to 180 so whats the angle of y?

Answer 5

Is it 55

Answer 6

well 55 plus 45 = 100 so 180 minus 100 equal 80.

Answer 7

Ok

Answer 8

sum of interior angles in a triangle, as @DisCrazyGinger said, is 180

so.. notice the "given" angles already, all that's missing is "y",
if one is 45 and the other 55, what is "y" for the sum to be 180?

Answer 9

@DisCrazyGinger

Answer 10

I think it's like 80

Answer 11

Yep 80 is correct

Answer 12

Ok thanks!