9.1.4 Explain Why an Expression Is a Perfect Square

Algebra 19.1.4 Explain Why an Expression Is a Perfect Square

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9.1.4 Explain Why an Expression Is a Perfect Square

9.1.4 • Explain Why an Expression Is a Perfect Square

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Explain why it makes sense to call the expression $x^{2} + 20 x + 100$ a perfect square.

Compare your answer:

It is equivalent to $(x + 10)^{2}$ , so it is a factor squared.

Solve $x^{2} + 20 x + 100 = 81$ .

Compare your answer:

$x = - 1$ and $x = - 19$

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