Question 253109


{{{(3a-1)^2}}} Start with the given expression.



{{{(3a-1)(3a-1)}}} Expand. Remember something like {{{x^2=x*x}}}.



Now let's FOIL the expression.



Remember, when you FOIL an expression, you follow this procedure:



{{{(highlight(3a)-1)(highlight(3a)-1)}}} Multiply the <font color="red">F</font>irst terms:{{{(3a)*(3a)=9a^2}}}.



{{{(highlight(3a)-1)(3a+highlight(-1))}}} Multiply the <font color="red">O</font>uter terms:{{{(3a)*(-1)=-3a}}}.



{{{(3a+highlight(-1))(highlight(3a)-1)}}} Multiply the <font color="red">I</font>nner terms:{{{(-1)*(3a)=-3a}}}.



{{{(3a+highlight(-1))(3a+highlight(-1))}}} Multiply the <font color="red">L</font>ast terms:{{{(-1)*(-1)=1}}}.



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So we have the terms: {{{9a^2}}}, {{{-3a}}}, {{{-3a}}}, {{{1}}} 



{{{9a^2-3a-3a+1}}} Now add every term listed above to make a single expression.



{{{9a^2-6a+1}}} Now combine like terms.



So {{{(3a-1)^2}}} FOILs to {{{9a^2-6a+1}}}.



In other words, {{{(3a-1)^2=9a^2-6a+1}}}.