Find the measure of angle B in isosceles triangle ABC.
Responses
A 65°65°
B 130°130°
C 55°55°
D 40°40°
E 85°
There is not enough information provided to determine the measure of angle B in isosceles triangle ABC.
In an isosceles triangle, the measure of the base angles are equal. Let's call the base angle B. Since angle A and angle C are equal, their sum must be equal to twice angle B.
Therefore, angle A + angle C = 2 * angle B
Given that angle A = 65° and angle C = 55°, we can substitute these values into the equation:
65° + 55° = 2 * angle B
120° = 2 * angle B
To solve for angle B, we divide both sides of the equation by 2:
120° / 2 = angle B
60° = angle B
Therefore, angle B measures 60°.