Calculate the area of a circle with a diameter of 6cm

Area of circle = πd²/4,    where d = diameter
 
                      = π*6*6/4 = 9π ≈ 9 *3.1416 ≈ 28.2744 cm²

Area ≈ 28.27 cm²

Hope this explains it.

A≈28.27cm² is the area of the circle with diameter 6cm
as
 Area of a circle = pi * r² 

Since the diameter is twice the radius, the radius is 6cm/2 which is 3cm. 

pi * 3 * 3 

= 28.2743339cm²

Okay so for every triangle has three angles that always add up to 180 degrees. and to tell the difference between whether they are secure, right or obtuse is that acute: has one angle that is less than 90 degrees. right triangle means there is at least one angle that is exactly 90 degrees. and an obtuse angle has an angle that is bigger than 180 degrees. i’ll do #13 as an example: 13. 40 and 50 so if every triangle has 180 degrees 40+50= 90 degrees then180-90= 90 degrees so the third angle is 90 degrees and because this triangle has a 90 degree angle it means it is a right triangle

What mathematical statement is missing ? ? the answer is b