GCSE Secondary Maths Age 13-17 - Geometry & Measures: Area - Triangles and Quadrilaterals - Explained

The video tutorial explains how to calculate the area of a right-angled triangle with sides in the ratio of 3:4:5. It begins by determining the actual side lengths using the given perimeter of 72 cm. The process involves dividing the perimeter according to the ratio, resulting in side lengths of 18 cm, 24 cm, and 30 cm. The area is then calculated using the formula for the area of a triangle: base multiplied by height divided by two. The tutorial also outlines the marking scheme for the problem, emphasizing the importance of understanding ratios and basic arithmetic operations.

What is the ratio of the sides of the triangle discussed in the video?

• 1:2:3

• 3:4:5

• 5:12:13

• 2:3:4

If the perimeter of the triangle is 72 cm, what is the length of the side with the ratio 3?

• 24 cm

• 30 cm

• 36 cm

• 18 cm

How do you calculate the actual length of the sides from the given ratio?

• Subtract the smallest ratio part from the perimeter

• Divide the perimeter by the sum of the ratio parts and multiply by each part

• Multiply the ratio by the perimeter

• Add the ratio parts and multiply by the perimeter

What formula is used to calculate the area of the triangle?

• Base multiplied by height

• Base multiplied by height divided by two

• Product of all sides divided by two

• Sum of all sides

How many marks were allocated for finding the correct area of the triangle?

• Four marks

• One mark

• Two marks

• Three marks