Lam would like to run a hall-marathon, which is a distance of 21 km . How many times would he have to run arbund his schoors athletics track (which measures 400 melres) in order to at least equal the distance of a hall-marathon?

a función racional \( f(x)=\frac{3 x^{2}+5 x+1}{(x+1)\left(x^{2}+3\right)} \). Al realizar la descomposición en fraciones parciales tenemos la siguiente forma.

\( \rightarrow \) Squalución \( \begin{array}{l}4 x-2 y=-2 \\ 2 x+3 y=-1\end{array} \)

Question 4 How many positive integers \( N \) satisfy the following equation. \[ 441-42 N+N^{2}=64 \]

Dos: Resolver problema utilizando a propriedade dos polígonos (soma de seus ângulos internos, número de diagonais, cálculo da medida de cada ângulo interno nos polígonos regulares).

\( \frac{\pi}{4} y-\frac{9}{4} \pi \) tienen el mismo lado terminal.