Question

If AB is parallel to CD, and angle ECO = 135°, and angle EAB = 130°, what is the value of x?

a. 5°

b. 10°

c. 15°

d. 20°

Answer 1

To find the value of x, subtract the measure of angle ECO from angle EAB to find the measure of angle OCB. Then, use the properties of parallel lines to determine that angle OCB is congruent to angle ABD, meaning x = 175°.

Step-by-step explanation:

To find the value of x, we need to use the properties of parallel lines and angles. Since AB is parallel to CD, the alternate interior angles are congruent. Therefore, angle EAB is also 130°. We can subtract angle ECO from angle EAB to find the measure of angle OCB: 130° - 135° = -5°. However, angles cannot be negative, so we add 180° to -5° to get 175°.

Since AB is parallel to CD, angle OCB must be congruent to angle ABD. Therefore, x = 175°.