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GCSE maths question

The size of a Tv screen is the length of the diagonal. An 80cm TV screen has an area of 2700cm squared.

Work out the length of the diagonal of a Tv screen with double the area
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Moe_00
15
The scale factor between the two TVs is given to you. However this is a scale factor in area, and you want it for the length. The unit for length is in cm, the unit for area is cm squared. As you want to go from cm^2 to cm you need to square root your scale factor.
The rest of the question is a simple ratios question.
I call this topic L A V
There is a relationship, in similar shapes, between the Scale factor for Length, Area & Volume.

So, for example, if one solid has lengths three times the corresponding lengths of a similar, smaller shape,

its surface Area will be 3squared = 9 times the surface area of the smaller solid

its Volume will be 3cubed = 27 times the volume of the smaller shape.

Is this enough for you to attempt your question on TV sizes?

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