Question 550665


{{{(3r+8)^2}}} Start with the given expression.



{{{(3r+8)(3r+8)}}} 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(3r)+8)(highlight(3r)+8)}}} Multiply the <font color="red">F</font>irst terms:{{{(3*r)*(3*r)=9*r^2}}}.



{{{(highlight(3r)+8)(3r+highlight(8))}}} Multiply the <font color="red">O</font>uter terms:{{{(3*r)*(8)=24*r}}}.



{{{(3r+highlight(8))(highlight(3r)+8)}}} Multiply the <font color="red">I</font>nner terms:{{{(8)*(3*r)=24*r}}}.



{{{(3r+highlight(8))(3r+highlight(8))}}} Multiply the <font color="red">L</font>ast terms:{{{(8)*(8)=64}}}.



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So we have the terms: {{{9*r^2}}}, {{{24*r}}}, {{{24*r}}}, {{{64}}} 



{{{9*r^2+24*r+24*r+64}}} Now add every term listed above to make a single expression.



{{{9r^2+48r+64}}} Now combine like terms.



So {{{(3r+8)^2}}} FOILs to {{{9r^2+48r+64}}}.



In other words, {{{(3r+8)^2=9r^2+48r+64}}}.