Step-by-step explanation:
a. Area of a circle = πr², where r means radius.
Step 1: converted diameter to radius.
diameter = 2 radius
In other way of writing, radius = diameter.
Step 2: substitute radius into the formula.
Area of a circle = π(d)²
Step 3: substitute π into the formula.
some question is given the value of π), if not substitute 3.14 for π.
Area of a circle = 3.14(d)²
Step 4: substitute d into the formula, then we can solve its area.
b. a. Circumference of a circle = 2πr, where r means radius.
Step 1: converted diameter to radius.
diameter = 2 radius
In other way of writing, radius = diameter.
Step 2: substitute radius into the formula.
C = 2π(d)
Step 3: substitute π into the formula.
some question is given the value of π), if not substitute 3.14 for π.
C = 2(3.14)(d)
Step 4: substitute d into the formula, then we can solve its circumference.