Answer:
D) 49°
Explanation:
According to Angle Subtended by the Same Arc Theorem, the angles at the circumference subtended by the same arc are equal.
Therefore, for the given circle, ∠J = ∠I.
First find the value of x by equating the expressions for angles J and I:
⇒ ∠J = ∠I
⇒ (10x - 1)° = (8x + 9)°
⇒ 10x - 1 = 8x + 9
⇒ 10x - 1 - 8x = 8x + 9 - 8x
⇒ 2x - 1 = 9
⇒ 2x - 1 + 1 = 9 + 1
⇒ 2x = 10
⇒ 2x/2 = 10/2
⇒ x = 5
To find the measure of angle J, substitute the found value of x into the expression for ∠J:
⇒ ∠J = (10x - 1)°
⇒ ∠J = (10(5) - 1)°
⇒ ∠J = (50 - 1)°
⇒ ∠J = 49°
Therefore, the measure of ∠J is 49°.