Area of Triangles & Quadrilaterals (Using Formulas)

Area is the amount of space inside a shape. Area is measured using square units. Perimeter is the distance around a shape and is measured in units.

48 sq. cm.

Kamal is not correct. The area of this rectangle is 6 cm × 5 cm = 30 sq. cm. It looks like Kamal found the perimeter instead of the area.

The area of a triangle is half the area of a rectangle with the same base and height.

I can divide the shape into one or more rectangles and right triangles. I can calculate the area of each sub-shape and then add the areas together to find the total area.

The formula is A=[ggfrac]1/2[/ggfrac]bh. The area of this triangle is 54 sq. in.

The formula is A = bh. The area of the parallelogram is 15 sq. m.

The formula is A=[ggfrac]1/2[/ggfrac](b1+b2)h. The area is 73.5 sq. cm.

Answer will vary. Students may discuss how a non-right triangle can be divided into two right triangles and that makes the same formula. They may discuss how a parallelogram can be transformed into a rectangle.

No, Jasmine is not correct. She multiplied the base (6 units) by the length of one of the sides (4.5 units). She should have multiplied the base (6 units) by the height (4 units). 6 × 4 = 24. The correct answer is 24 square units.