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1 vote
Fill in the blank with a number to make the expression a perfect square y^2 -18y+

User JVillella
by
6.9k points

1 Answer

5 votes

Given,

The expression is,


y^2-18y+--

Required

The perfect square of the expression.

To make the perfect square add 81 to the expression.


\begin{gathered} y^2-18y+81 \\ =(y)^2-2* y*9+(9)^2 \\ =(y-9)^2 \end{gathered}

hence, it is required to add 81.

User Florian Bernard
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7.4k points