Find the perimeter of the following shape.
An isosceles triangle with a base of 7cm and the two equal sides of 5 cm each

Answer

To find the perimeter of the isosceles triangle with a base of 7 cm and two equal sides of 5 cm each, we can follow these steps:

### Step 1: Identify the lengths of the sides
- The base (b) of the triangle is given as 7 cm.
- The lengths of the two equal sides (a) are given as 5 cm each.

### Step 2: Write the formula for the perimeter of an isosceles triangle
- The formula for the perimeter (P) of an isosceles triangle is:
\[ P = 2a + b \]
where \( a \) is the length of the equal sides and \( b \) is the length of the base.

### Step 3: Substitute the values into the formula
- Here, \( a = 5 \) cm and \( b = 7 \) cm.
- Substitute these values into the formula:
\[ P = 2(5) + 7 \]

### Step 4: Calculate the perimeter
- First, calculate \( 2(5) \):
\[ 2(5) = 10 \]
- Now add the base:
\[ P = 10 + 7 = 17 \text{ cm} \]

### Final Answer
- The perimeter of the isosceles triangle is **17 cm**.

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