a) The equation is 20x + 21 = 30x − 29 and the value of x is 5.
b) The measures of both angles is 121°.
Explanation:
The drawing shown contains the intersection of two lines.
- Two intersecting lines form a pair of vertical angles.
- The vertical angles are opposite angles and are equal in measure.
- Here, ∠1 and ∠2 are vertical angles and are equal to each other.
a) To create an equation to find the measures of both angles:
Since both the angles are equal, the equation can be framed as ∠1 = ∠2 .
⇒ 20x + 21 = 30x − 29
Bring x terms alone on one side of the equation,
⇒ 21 + 29 = 30x - 20x
⇒ 50 = 10x
Divide by 10 on both sides of the equation,
⇒ 50 / 10 = x
⇒ x = 5
∴ The value of x is 5.
b) To find the measures of both angles :
The measure of ∠1 = 20x + 21
Substitute x= 5,
⇒ 20(5) + 21
⇒ 100 + 21
⇒ 121
∴ The measure of ∠1 is 121°
The measure of ∠2 = 30x − 29
Substitute x= 5,
⇒ 30(5) - 29
⇒ 150 - 29
⇒ 121
∴ The measure of ∠2 is 121°