Question 1062328
Notice that 144 is a perfect square (12*12)
and that 9p^2 is also a perfect square ((3p)(3p))...

When you have the form {{{ a^2-b^2}}} (i.e. the difference between two squares) you can factor it to          {{{ (a+b)(a-b) }}}  (I encourage you to multiply (a+b)(a-b) out for yourself to see that you indeed get {{{a^2-b^2}}}

If I let a=12 and b=3p:

{{{ (12-3p)(12+3p) = 144-9p^2 }}}

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Depending on how far you want to take it, a "3" can be factored out from each of the above factors:

  = {{{ 3*3*(4-p)(4+p) }}} = {{{ 9*(4-p)(4+p) }}}