In a rhombus ABCD, if `angleA=60^(@)` find `angleB, angleC&angleD`.

Answer

To solve the problem, we need to find the measures of angles B, C, and D in rhombus ABCD, given that angle A = 60°.

### Step-by-Step Solution:

1. **Understand the properties of a rhombus**:
- In a rhombus, opposite angles are equal, and adjacent angles are supplementary (they add up to 180°).
- Therefore, if angle A = 60°, then angle C (the opposite angle) will also be 60°.

**Hint**: Remember that in a rhombus, opposite angles are equal.

2. **Calculate angle B**:
- Since angles A and B are adjacent, we can use the property that they are supplementary:
\[ \text{Angle A} + \text{Angle B} = 180° \]
\[ 60° + \text{Angle B} = 180° \]
\[ \text{Angle B} = 180° - 60° = 120° \]

**Hint**: Use the supplementary angle property (angles that add up to 180°) for adjacent angles.

3. **Calculate angle D**:
- Similarly, angle D is opposite to angle B, so:
\[ \text{Angle D} = \text{Angle B} = 120° \]

**Hint**: Remember that opposite angles in a rhombus are equal.

4. **Summarize the angles**:
- We have found:
- Angle A = 60°
- Angle B = 120°
- Angle C = 60°
- Angle D = 120°

**Hint**: Always check that the sum of all angles in a quadrilateral equals 360°.

### Final Answer:
- Angle B = 120°
- Angle C = 60°
- Angle D = 120°