If the perimeter of triangle DEF is 36 cm and the lengths of sides DE and EF are

If the perimeter of triangle DEF is 36 cm and the lengths of sides DE and EF are 10 cm and 12 cm respectively, what is the length of side DF? (2020)

If the perimeter of triangle DEF is 36 cm and the lengths of sides DE and EF are 10 cm and 12 cm respectively, what is the length of side DF? (2020)

Step 1: Understand that the perimeter of a triangle is the total length around the triangle, which is the sum of all its sides.
Step 2: Identify the lengths of the sides given in the problem: DE is 10 cm and EF is 12 cm.
Step 3: Add the lengths of sides DE and EF together: 10 cm + 12 cm = 22 cm.
Step 4: Use the formula for the perimeter of the triangle: Perimeter = DE + EF + DF.
Step 5: Substitute the known values into the perimeter formula: 36 cm = 10 cm + 12 cm + DF.
Step 6: Simplify the equation: 36 cm = 22 cm + DF.
Step 7: To find DF, subtract 22 cm from 36 cm: DF = 36 cm - 22 cm.
Step 8: Calculate the result: DF = 14 cm.

Perimeter of a Triangle – Understanding that the perimeter is the sum of all sides of a triangle.
Algebraic Manipulation – Ability to rearrange equations to solve for an unknown variable.