6 — Triangle Areas

Triangle Areas

Solution & Explanation · ID: DC1240C4

Question

Sarah wants to plant grass in her triangular backyard. The triangle has a base of 18 feet and a height of 12 feet. How many square feet of grass seed does she need?

Hint

This is asking for the area of the triangular yard. Use the triangle area formula.

Concept

Real-world triangle area problems use the same formula. Sarah needs to find the area of her triangular backyard to determine how much grass seed to buy.

Show Answer

108 square feet

Show Solution
1

Identify the backyard dimensions: base = 18 feet, height = 12 feet

2

Use the triangle area formula: A = ½ × base × height

3

Substitute the values: A = ½ × 18 × 12

4

Calculate: A = ½ × 216 = 108 square feet

5

Sarah needs 108 square feet of grass seed

A triangle representing Sarah's backyard with base labeled '18 ft' along the bottom edge. A dashed vertical line shows the height labeled '12 ft' perpendicular to the base. Inside the triangle is written 'Grass area = 108 sq ft'. Small grass symbols are scattered inside the triangle. The calculation A = ½ × 18 × 12 = 108 is shown below.