So.... notice the picture below

now, we know what the "height" or "altitude" is
now, we also know the perimeter is 18cm

so, k + k + b = 18
or 2k + b = 18
thus $\bf k=\cfrac{18-b}{2}$

so... one can say that $\bf \textit{area of a triangle}=A=\cfrac{1}{2}bh\qquad 
\begin{cases}
b=b
\\\\
h=\sqrt{k^2-\left( \frac{b}{2} \right)^2}
\\\\
h=\sqrt{k^2-\frac{b^2}{4}}\\
--------------\\
k=\frac{18-b}{2}\qquad thus\\
--------------\\
h=\sqrt{\left( \frac{18-b}{2} \right)^2-\frac{b^2}{4}}
\end{cases}\\\\
-----------------------------\\\\
A=\cfrac{1}{2}\cdot b\cdot \sqrt{\left( \frac{18-b}{2} \right)^2-\frac{b^2}{4}}$

and you can simplify it if you wish.. not sure you have to

7 0

2 years ago

A train is traveling from New Orleans in Memphis at a constant speed of 79 miles per hour. New Orleans and Memphis are 395.1 mil

Ket [755]

To calculate the time it will take, take the distance between Memphis and New Orleans and divide it by the speed at which the train is traveling: 395.1 / 79
The answer you will get is 5.001

3 0

3 years ago