Part a: Option c:
Part b: The value of x is 26
Explanation:
Part a:
Option a:
Since, adding all the angles in the straight line results in 180°, and only two of the three angles were added in the equation to find the value of x.
Thus, the equation cannot be used to determine the value of x.
Hence, Option a is not the correct answer.
Option b:
Adding all the angles in the straight line results in 180°.
Thus, adding all the angles does not equals to 90°
Hence, the equation cannot be used to determine the value of x.
Hence, option b is not the correct answer.
Option c:
Since, the straight line is 180° and thus adding the angles in this straight line will result in 180°
Thus, the angles in this straight line are 3x, 90° and x-14.
Hence, adding these angles will result in 180°
Thus, the equation becomes
Hence, the equation used to determine the value of x is
Thus, Option c is the correct answer.
Option d:
Adding all the angles in the straight line results in 180°.
Since, not all the three angles were added in this equation and the equation equals to 180°
Hence, the equation cannot be used to determine the value of x.
Thus, Option d is not the correct answer.
Part b:
To determine the value of x, we shall add all the angles of the equation
Thus, we get,
Subtracting both sides by 76,
Dividing both sides by 4, we get,
Thus, the value of x is 26.
