Question

Use the relationship between the angles in the figure to answer the question.

Which equation can be used to find the value of x?

x+49−28=180
​x−49−28=180
​x + 49 + 28 = 180​
​x + 28 = 180​

Three lines making six angles with the top left angle at twenty eight degrees, the top right angled at forty nine degrees and the bottom middle angle at x degrees

Answer 1

​x + 49 + 28 = 180​

Explanation:

THIS ANSWER IS CORRECT

Answer 2

​x + 49 + 28 = 180​

Explanation:

​The angles on a straight line with x° are 28° and 49° respectively, side by side with x°. This is because, vertical angles are equal. Therefore, the angle vertically opposite 28° and 49° are equal to 28° and 49° respectively.

Therefore, since angles on a straight line is 180°, thus:

​x + 49 + 28 = 180​