What value(s) of x make the equation x² - 18x + 81 = 0 true?

Solution:

The given equation is quadratic in form.

x² - 18x + 81 = 0

Splitting the middle term

x² - 9x - 9x + 81 = 0

Taking out the common terms

x(x - 9) - 9(x - 9) = 0

So we get

(x - 9)(x - 9) = 0

(x - 9)² = 0

Taking square root on both sides

x - 9 = 0

x = 9

Therefore, the value of x is 9.

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What value(s) of x make the equation x² - 18x + 81 = 0 true?

Summary:

The value of x which makes the equation x² - 18x + 81 = 0 true is 9.