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)
Practice Questions
1 question
Q1
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)
10 cm
12 cm
14 cm
16 cm
Perimeter = DE + EF + DF. Therefore, DF = 36 - (10 + 12) = 14 cm.
Questions & Step-by-step Solutions
1 item
Q
Q: 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)
Solution: Perimeter = DE + EF + DF. Therefore, DF = 36 - (10 + 12) = 14 cm.
Steps: 8
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.
