Formula for ratio of trapezium areas

[jlloyd]

Hi,

The formula for the area of a trapezium is 1/2(a+b)h, where a and b are the length of the two parallel sides and h is the length of the normal to these sideds between these two sides.

If the area of a trapezium is A and I reduce the area to B by decreasing h to h_new, what is the formula for h_new in terms of a, b, h and B?

I really have tried this and I end up with a horrible quadratic.

Is this a simple thing and I am missing the obvious, or is it actually really difficult?

Many thanks.

 

[Deleted member 4993]

Hi,

The formula for the area of a trapezium is 1/2(a+b)h, where a and b are the length of the two parallel sides and h is the length of the normal to these sideds between these two sides.

If the area of a trapezium is A and I reduce the area to B by decreasing h to h_new, what is the formula for h_new in terms of a, b, h and B?

I really have tried this and I end up with a horrible quadratic.

Is this a simple thing and I am missing the obvious, or is it actually really difficult?

Many thanks.

I do not get a quadratic.

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