c) The shape is a triangle with side lengths 3 cm, 4 cm, and 5 cm.
Step 1: Identify the formula for the perimeter of a triangle.
The perimeter P of a triangle with side lengths a, b, and c is given by:
P=a+b+c
Step 2: Substitute the given side lengths into the formula.
P=3cm+4cm+5 cm
Step 3: Calculate the perimeter.
P=12 cm
The perimeter of the triangle is 12cm.
d) The shape is a circle with a radius of 3 cm.
Step 1: Identify the formula for the perimeter (circumference) of a circle.
The circumference C of a circle with radius r is given by:
C=2πr
Step 2: Substitute the given radius into the formula.
C=2×π×3 cm
Step 3: Calculate the circumference.
C=6π cm
Using π≈3.14159:
C≈6×3.14159 cm
C≈18.85 cm
The perimeter (circumference) of the circle is 6πcm or approximately 18.85cm.
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