Question

An isosceles triangular score board of a ground with base 25m and two of its equal sides are 18m. How much electric wire will be needed to fix all around to illuminate it?
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Answer 1

Answer:

The two equal sides of an isosceles triangle with fixed base b are decreasing at the rate of 3 cm per second. How fast is the area decreasing when the two equal sides are equal to the base ?

A

Let x be the equal sides of isosceles triangle

i.e. AB = AC = x

X

X

And, Base= BC = b

B

b

Given that equal side of Triangle decreasing at 3 cm per second

dx - dt i.e. - 3 cm/sec.

We need to find how fast is the area decreasing when the two equal sides are equal to the base