Answer:
see explanation
Step-by-step explanation:
The area (A) of a triangle is calculated as
A = [tex]\frac{1}{2}[/tex] bh ( b is the base and h the perpendicular height )
(1)
b = 6 and h = 9 , then
A = [tex]\frac{1}{2}[/tex] × 6 × 9 = 3 × 9 = 27 cm²
(2)
b = 3 and h = 5 , then
A = ×[tex]\frac{1}{2}[/tex] × 3 × 5 = 1.5 × 5 = 7.5 cm²
(3)
b = 6 and h = 10 , then
A = [tex]\frac{1}{2}[/tex] × 6 × 10 = 3 × 10 = 30 cm²
(4)
b = 8 and h = 14 , then
A = [tex]\frac{1}{2}[/tex] × 8 × 14 = 4 × 14 = 56 cm²
(5)
b = 7 and h = 9 , then
A = [tex]\frac{1}{2}[/tex] × 7 × 9 = 3.5 × 9 = 31.5 cm²
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The figures are composed of a rectangle and a triangle
The area is the sum of the areas of the rectangle and the triangle
A = (5 × 4) + [tex]\frac{1}{2}[/tex] × 5 × 4
= 20 + 10
= 30 cm²
(2)
A = (7 × 5) + [tex]\frac{1}{2}[/tex] × 7 × 2
= 35 + 7
= 42 cm²
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The area (A) of a trapezium is calculated as
A = [tex]\frac{1}{2}[/tex] h (a + b)
where h is the perpendicular height and a, b the parallel bases
(1)
A = [tex]\frac{1}{2}[/tex] × 5 × (7 + 11) = 2.5 × 18 = 45 cm²
(2)
A = [tex]\frac{1}{2}[/tex] × 6 × (6.6 + 8.4) = 3 × 15 = 45 cm²
(3)
A = [tex]\frac{1}{2}[/tex] × 4.3 × (9.1 + 7.1) = 2.15 × 16.2 = 34.83 cm²
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The figure consists of a rectangle in the middle and 2 trapezium at the ends
A = [tex]\frac{1}{2}[/tex] �� 6 × (10 + 12) + (12 × 15) + [tex]\frac{1}{2}[/tex] × 11 × (12 + 9)
= 3 × 22 + 180 + 5.5 × 21
= 66 + 180 + 115.5
= 361.5 m²
Divide by 20 to find number of cans required
361.5 ÷ 20 = 18.075
Only whole tins can be bought , so 19 tins required
cost = 19 × £6 = £114
