ABC is a triangle in which AB = AC = 4 cm and `angleA=90^(@)`. Calculate:
the area of `DeltaABC`,

Answer

To find the area of triangle ABC where AB = AC = 4 cm and angle A = 90°, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Type of Triangle**:
Since AB = AC and angle A = 90°, triangle ABC is an isosceles right triangle.

2. **Understand the Formula for Area**:
The area \( A \) of a triangle can be calculated using the formula:
\[ A = \frac{1}{2} \times \text{base} \times \text{height} \]
In this case, we can take AB as the height and AC as the base.

3. **Substitute the Values**:
We know that:
- AB = 4 cm (height)
- AC = 4 cm (base)

Substituting these values into the area formula gives:
\[ A = \frac{1}{2} \times 4 \times 4 \]

4. **Calculate the Area**:
Now, calculate the area:
\[ A = \frac{1}{2} \times 4 \times 4 = \frac{1}{2} \times 16 = 8 \text{ cm}^2 \]

5. **Final Result**:
Therefore, the area of triangle ABC is:
\[ \text{Area} = 8 \text{ cm}^2 \]