# SOLUTION: dear tutor: please help! i have a question where x = 2,4,6,8,10 and y = 3,8,15,24,35. what would the equation be that would match this graph? thanks, joe

Algebra ->  -> SOLUTION: dear tutor: please help! i have a question where x = 2,4,6,8,10 and y = 3,8,15,24,35. what would the equation be that would match this graph? thanks, joe      Log On

 Ad: Mathway solves algebra homework problems with step-by-step help! Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

 Question 120149: dear tutor: please help! i have a question where x = 2,4,6,8,10 and y = 3,8,15,24,35. what would the equation be that would match this graph? thanks, joeAnswer by scott8148(6628)   (Show Source): You can put this solution on YOUR website!the differences in x are constant (2) the differences in y are 5, 7, 9, 11 __ but the differences in the differences are constant (2) this indicates a second order (squared) relation y=ax^2+bx+c for (2,3) 3=4a+2b+c for (4,8) 8=16a+4b+c for (6,15) 15=36a+6b+c subtracting first from second gives 5=12a+2b (A) subtracting second from third gives 7=20a+2b (B) subtracting (A) from (B) gives 2=8a, so a=.25 substituting gives 5=12(.25)+2b __ 2=2b __ 1=b substituting gives 3=4(.25)+2(1)+c __ 3=1+2+c __ 0=c y=.25x^2+x