Evaluate the expression `2ab + 7bc ` when `a = 2, b = 3 and c = 4`.

Answer

To evaluate the expression \(2ab + 7bc\) when \(a = 2\), \(b = 3\), and \(c = 4\), follow these steps:

### Step 1: Substitute the values of \(a\), \(b\), and \(c\) into the expression.
The expression is:
\[ 2ab + 7bc \]
Substituting the values:
\[ 2(2)(3) + 7(3)(4) \]

### Step 2: Calculate the first part of the expression \(2ab\).
Calculate \(2(2)(3)\):
\[ 2 \times 2 = 4 \]
\[ 4 \times 3 = 12 \]
So, \(2ab = 12\).

### Step 3: Calculate the second part of the expression \(7bc\).
Calculate \(7(3)(4)\):
\[ 7 \times 3 = 21 \]
\[ 21 \times 4 = 84 \]
So, \(7bc = 84\).

### Step 4: Add the results from Step 2 and Step 3.
Now, add \(12\) and \(84\):
\[ 12 + 84 = 96 \]

### Final Answer:
The value of the expression \(2ab + 7bc\) when \(a = 2\), \(b = 3\), and \(c = 4\) is \(96\).

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