# Thread: Finding the length of a line

1. ## Finding the length of a line

Hello again everyone.

A few days ago I posted a query regarding how to find the width of ‘similar’ shapes using ratio and proportion (please see the bottom of this post for a recap of this question). I was very kindly told how to solve this; however, I have another maths problem which is related to my previous one.

The problem is this (please click below image)…

On the left is a rectangle, its height is 7.3cm and its width 5.1cm. Inside this rectangle is a blue five-sided shape. One of the sides of this shape is marked A to B with the length of this line being 5cm.

To the right is the same rectangle with the same shape inside – only larger. This time the rectangle’s height is 10.9cm and its width is 7.6cm. However, the length of the AB line of this five-sided shape is unknown. Therefore I would like to know how to find the length of this AB line using the information given by the left rectangle/shape.

Can someone please show me how to do this as simply as possible (imagine you’re explaining it to a six year old) as well as showing me the steps toward the solution so I can work it out longhand.

Thanks for your time

Christopher

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Hello everyone

I’m very much a layman when it comes to mathematics and my education in this subject is quite poor, so I was wondering if someone could help me solve a maths problem?

The problem is this (please click below image)…

Above, on the left, is a diagram of a rectangle; its height is 7.3cm and its width is 5.1cm. To the right is the same rectangle - only larger, with a height of 10.9cm. However, the width of this second rectangle is unknown.

Therefore, I would like to know how to find the width of this second rectangle using the length and width of the first rectangle. Would someone kindly show me how to do this as simply as possible as well as showing me the steps toward the solution so I can work it out longhand.

Anyone?