Plz help. I can't figure it out. ​

Pelle's sister is three years older than pelle the father is 5 times as old as pelle the mother was 28 when the sister was born altogether they are 98 years old how old is pelle?

In two or more complete sentences describe how to determine the appropriate model for the set of data, (1,1), (3,2), (6,3), (11,4).

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)