Ineed to know what the area of a triangle is with a base of 27 ft and a height of 12 ft? i took 12x27=324/2 = 162 and i don't have a clue if that is how you do it. ….. chrissy

Based on what I learned in school, your answer should be correct. I double checked the calculations:)

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb