Question 102564
Let {{{t=x^2}}}


So we now get


{{{16t^2 - 40t + 9}}}


*[invoke change_this_name4450 16, -40, 9, "t"]



Since {{{t=x^2}}}, we can replace each t with {{{x^2}}} to get 


{{{(4x^2-9)(4x^2-1)}}}