Find the difference of the squares of 42 and 38 .

Options

A. 320
B. 16
C. 432
D. None of these

Answer

To find the difference of the squares of 42 and 38, we can follow these steps:

### Step 1: Identify the numbers
We have two numbers: 42 and 38.

### Step 2: Use the difference of squares formula
The difference of squares can be calculated using the formula:
\[ a^2 - b^2 = (a - b)(a + b) \]
Here, \( a = 42 \) and \( b = 38 \).

### Step 3: Calculate \( a - b \) and \( a + b \)
- Calculate \( a - b \):
\[ 42 - 38 = 4 \]

- Calculate \( a + b \):
\[ 42 + 38 = 80 \]

### Step 4: Substitute into the formula
Now substitute the values into the formula:
\[ 42^2 - 38^2 = (42 - 38)(42 + 38) \]
\[ = 4 \times 80 \]

### Step 5: Calculate the product
Now calculate \( 4 \times 80 \):
\[ 4 \times 80 = 320 \]

### Final Answer
The difference of the squares of 42 and 38 is **320**.

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