Imaginen que un maratonista corre toda una carrera a una velocidad constante. después de dos horas lleva recorridos 22 km •¿cuánto tarda en correr los 42 km de la competencia?

For this case we have:

If after 2 hours the marathon runner has traveled 22 kilometers we have:

2h -----------> 22km

Applying a rule of three, we can know the time it takes to run 42km. So, we have:

2h -----------> 22km

x -------------> 42km

Where "x" is the time it takes to travel 42km. Resolving we have:

Thus, after 3.82 hours the marathon runner will travel 42km.

3.82 hours

logv3(x+2)=1

rewrite in exponential form:

logb(x) = y is equal to b^y =x

b = 3, y = 1

now solve for x:

3^1 = x+2)

x = 3-2

x = 1

see the picture for the graph.