What are some advantages of displaying the relationship between two quantities using a qualitative graph?

Ihave trouble finding the nth term of a linear sequence

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

Questions 7-8. use the following table to answer. year 2006 2007 2008 2009 2010 2011 2012 2013 cpi 201.6 207.342 215.303 214.537 218.056 224.939 229.594 232.957 7. suppose you bought a house in 2006 for $120,000. use the table above to calculate the 2013 value adjusted for inflation. (round to the nearest whole number) 8. suppose you bought a house in 2013 for $90,000. use the table above to calculate the 2006 value adjusted for inflation. (round to the nearest whole number)