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In a triangle ABC, sides AB and AC are o...

In a triangle ABC, sides AB and AC are of equal length. If `angleB=35^(@)`, find the measure of `angleA and angleC`.

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To solve the problem, we will follow these steps: ### Step 1: Understand the properties of the triangle We are given that triangle ABC has sides AB and AC of equal length. This means that triangle ABC is an isosceles triangle. In an isosceles triangle, the angles opposite the equal sides are also equal. ### Step 2: Identify the given information - Angle B = 35 degrees - Sides AB = AC (equal sides) ### Step 3: Use the property of isosceles triangles Since AB = AC, the angles opposite these sides must be equal. Therefore: - Angle C = Angle B = 35 degrees ### Step 4: Use the angle sum property of triangles The sum of the angles in a triangle is always 180 degrees. Therefore, we can write the equation: \[ \text{Angle A} + \text{Angle B} + \text{Angle C} = 180^\circ \] Substituting the known values: \[ \text{Angle A} + 35^\circ + 35^\circ = 180^\circ \] ### Step 5: Simplify the equation Combine the angles: \[ \text{Angle A} + 70^\circ = 180^\circ \] ### Step 6: Solve for Angle A To find Angle A, subtract 70 degrees from both sides: \[ \text{Angle A} = 180^\circ - 70^\circ \] \[ \text{Angle A} = 110^\circ \] ### Conclusion Thus, the measures of the angles in triangle ABC are: - Angle A = 110 degrees - Angle B = 35 degrees - Angle C = 35 degrees
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