The two equal sides of an isosceles triangle with fixed base `b` are decreasing at the rate of `3c m//sdot` How fast is the area decreasing when the two equal sides are equal to the base?

Explanation

`frac{{da}}{{dt}}=-3 {cm} / {sec}`



Allitude `h^{2}=a^{2}-b^{2} / 4`



`h^{2}=frac{4 a^{2}-b^{2}}{4} `


`h=frac{sqrt{4 a^{2}-b^{2}}}{2} `


`A=frac{1}{2} b h`


`A=frac{1}{2} b frac{sqrt{4 a^{2}-b^{2}}}{2}=frac{b}{4} sqrt{4 a^{2}-b^{2}} `


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