Here is trapezium ABCD - Edexcel - GCSE Maths - Question 19 - 2021 - Paper 1

Question 19

Here is trapezium ABCD.
The area of the trapezium is 66cm²
the length of AB: the length of CD = 2:3
Find the length of AB.
Worked Solution & Example Answer:Here is trapezium ABCD - Edexcel - GCSE Maths - Question 19 - 2021 - Paper 1
Find dimensions based on ratio

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Let the length of CD be 3x and the length of AB be 2x, where x is a common multiplier for the lengths.
Use area formula for trapezium

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The area of a trapezium is given by the formula:
ext{Area} = rac{1}{2} imes (AB + CD) imes ext{height}
Substituting values, we have:
66 = rac{1}{2} imes (2x + 3x) imes hFind height using trigonometry

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From triangle BCD, we can find the height (h) using the angle given:
sin(30^ ext{o}) = rac{h}{6}
So, h = 6 × sin(30°) = 6 × 0.5 = 3 cm.
Substitute height into area equation

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Substituting the height back into the area formula gives:
66 = rac{1}{2} imes (5x) imes 3
This simplifies to:
66 = rac{15x}{2}Solve for x

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Multiplying both sides by 2:
132=15x
Thus:
x = rac{132}{15} = 8.8$$Find length of AB

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As AB = 2x, we substitute:
AB = 2 imes 8.8 = 17.6 ext{ cm}$$.Join the GCSE students using SimpleStudy...
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