Example

Solving (x3)2=16(x - 3)^2 = 16 Using the Square Root Property

Solve (x3)2=16(x - 3)^2 = 16 by applying the Square Root Property to a squared binomial. The entire expression (x3)(x - 3) is treated as the quadratic term.

Apply the Square Root Property. Since the squared binomial is already isolated:

x3=±16x - 3 = \pm\sqrt{16}

Simplify. Because 1616 is a perfect square (42=164^2 = 16):

x3=±4x - 3 = \pm 4

Write as two separate equations and solve each:

x3=4    x=7x - 3 = 4 \implies x = 7

x3=4    x=1x - 3 = -4 \implies x = -1

Check both solutions by substituting into the original equation:

For x=7x = 7: (73)2=42=16(7 - 3)^2 = 4^2 = 16

For x=1x = -1: (13)2=(4)2=16(-1 - 3)^2 = (-4)^2 = 16

The solutions are x=7x = 7 and x=1x = -1. This example demonstrates that the Square Root Property applies to any expression of the form (binomial)2=k(\text{binomial})^2 = k, not just x2=kx^2 = k. When the squared expression is a binomial, applying the property produces an equation of the form xh=±kx - h = \pm\sqrt{k}, and a final step of adding hh to both sides isolates the variable.

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Updated 2026-04-21

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