its college algebra and it has to factor completely
2007-06-08 11:31:03 · 4 answers · asked by aherrera82 1 in Science & Mathematics ➔ Mathematics
wont it also work out as (4y-9)(16y^2-36y+81)
2007-06-08 12:01:17 · update #1
(4y-9)(4y+9)
2007-06-08 11:36:25 · answer #1 · answered by yerffej89 3 · 0⤊ 0⤋
This looks like a difference of two squares (16y^2 and 81). Remember that a difference of two squares always factors out in the pattern (A-B)(A+B) where A and B are the two square roots. So factoring will give you (4y-9)(4y+9).
2007-06-08 18:35:24 · answer #2 · answered by PhysicsPat 4 · 1⤊ 1⤋
You have a difference of squares there. That is not college algebra, it's 9th grade at most. You need to make it so that there is no middle term, so when you foil your binomials, you will get two opposites (which would add to zero).
(4y+9)(4y-9) is the way to do it
2007-06-08 18:38:52 · answer #3 · answered by MLBfreek35 5 · 0⤊ 1⤋
16y² - 81 = (4y - 9).(4y + 9)
This comes from result:-
a² - b² = a² - b²
(4y)² - 9² = (4y - 9).(4y + 9)
2007-06-09 04:53:42 · answer #4 · answered by Como 7 · 0⤊ 1⤋