Finding Lengths and Widths of Rectangles

The video tutorial covers lesson 12.3, focusing on finding unknown measures in geometry, specifically area and perimeter. The teacher introduces the concepts, provides examples, and engages students in class activities to determine missing measures. The lesson includes practice problems and advanced problems involving fractions, concluding with a summary of the key points.

What is the main focus of lesson 12.3?

• Learning about circles

• Studying fractions

• Understanding algebra

• Finding unknown measures

What is the formula for the area of a rectangle?

• Length - Width

• Length x Width

• Length + Width

• 2 x (Length + Width)

How do you calculate the perimeter of a rectangle?

• Multiply length by width

• Subtract width from length

• Divide length by width

• Add all the sides

If a rectangle has an area of 20 square units and a length of 5, what is the width?

• 2 units

• 3 units

• 5 units

• 4 units

A rectangle has a perimeter of 20 units and a width of 3. What is the length?

• 7 units

• 17 units

• 14 units

• 10 units

What is the missing length if the area of a rectangle is 36 square feet and the width is 3 feet?

• 12 feet

• 9 feet

• 10 feet

• 11 feet

If the perimeter of a rectangle is 30 cm and the length is 16 cm, what is the width?

• 10 cm

• 9 cm

• 8 cm

• 7 cm

What is the length of a rectangle if the area is 75 square units and the width is 5 units?

• 10 units

• 18 units

• 12 units

• 15 units

For a rectangle with a perimeter of 42 units and one side of 12 units, what is the length of the other side?

• 10 units

• 9 units

• 8 units

• 6 units

If a rectangle has an area of 50 square mm and a width of 2 mm, what is the length?

• 22 mm

• 20 mm

• 24 mm

• 25 mm