Explanation
In geometry, the area enclosed by a triangle is defined by this formula:
where b represents the base of the triangle, and h represents the height, measured at right angles to the base. In Excel, the same formula can be represented like this:
A=b*h/2
So, for example, to calculate the area of a triangle with a base of 4 and a height of 3:
=4*3/2 // returns 6
In the example shown, the goal is to calculate the area for eleven triangles with base given in column B and height given in column C. The formula in D5 is:
=(B5*C5)/2
As this formula is copied down the table, it calculates a different area at each new row.
Note: The parentheses in this formula are optional and for readability only. In Excel’s order of operations , multiplication will occur before division, so the parentheses are unnecessary.
Explanation
In geometry, the circumference of a circle with radius (r) is defined by the following formula: =2πr
The Greek letter π (“pi”) represents the ratio of the circumference of a circle to its diameter. In Excel, π is represented in a formula with the PI function , which returns the number 3.14159265358979, accurate to 15 digits.
=PI() // returns 3.14159265358979
Therefore, the formula to calculate the circumference of a circle with a radius of 3 is:
=2*PI()*3 // returns 18.85
And the formula to calculate circumference based on the radius values in column B, is:
=2*PI()*B5
