Here is a rectangle - Edexcel - GCSE Maths - Question 6 - 2017 - Paper 3
Question 6
Here is a rectangle.
The length of the rectangle is 7cm longer than the width of the rectangle.
4 of these rectangles are used to make this 8-sided shape.
The per... show full transcript
Worked Solution & Example Answer:Here is a rectangle - Edexcel - GCSE Maths - Question 6 - 2017 - Paper 3
Step 1
The length of the rectangle is 7cm longer than the width of the rectangle.
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Answer
Let the width of the rectangle be denoted as w. Then, the length can be expressed as w+7. Since 4 rectangles form the 8-sided shape, the contributions to the perimeter must be considered.
Step 2
The perimeter of the 8-sided shape is 70cm.
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Answer
The 8-sided shape consists of 4 rectangles. The perimeter can be calculated using the formula:
egin{align*}
P &= 2( ext{lengths}) + 2( ext{widths})
&= 2(4(w + 7)) + 2(4w)
&= 8w + 56 + 8w
&= 16w + 56 = 70
ext{Now, solve for } w:
16w = 70 - 56
16w = 14
w = rac{14}{16} = 0.875
ext{Thus, the width } w = 3.5 ext{ cm and the length } l = 10.5 ext{ cm.}
dimensionally: w = 3.5 ext{ cm, } l = w + 7 = 10.5 ext{ cm.}
Step 3
Work out the area of the 8-sided shape.
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Answer
The area of one rectangle is given by
A=extwidthimesextlength=3.5imes10.5
Therefore, the area of one rectangle is:
A=3.5imes10.5=36.75extcm2
Since there are 4 rectangles, the total area of the 8-sided shape is:
extTotalArea=4imes36.75=147extcm2