# Simple function/variable problem

1. Jan 25, 2009

### wallace13

The base of an isosceles triange has length b and the two sides of equal length each measure 30 cm. Find the area A of the triangle as a function of b.

a squared + b squared = c squared
Area= .5bh

.5b squared + h squared = 30 squared
h= (-.5b squared + 900) ^ 1/2

Area= .5 x b x [(-.5b squared + 900)^ 1/2]

Is this correct?

2. Jan 26, 2009

### Gib Z

Well it is sort of ambiguous what you mean by the -.5b squared, but if you meant

$$A = \frac{b}{2} \cdot \sqrt{ 900 - \frac{b^2}{4} }$$

as you probably did, then yes, its correct ! =]