Originally Posted by

**pstutts17** ok well the problem is i have to figure out how the step number is related to the number of tiles in the fig. and write an equation for how they are related so here are the numbers

in the first step there is one tile

in the second step there are three tiles

in the third step six tiles

in the fourth step 10 tiles

in the fith step 15 tiles

and so on

i understand that they increase by the amount in the prevoious plus the new number but i need to no how to write the equation