How do you solve this equation using the square root property ${(x + 7)}^{2} = 81$ $(x + 7)^2 = 81$ ?

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How do you solve this equation using the square root property ${(x + 7)}^{2} = 81$ $(x + 7)^2 = 81$ ?

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Answer 1 · 2015-08-13T15:27:12

The solutions are
$x = 2, x = - 16$ $color(blue)(x=2,x=-16$

Explanation:

The square root property involves taking the square root of both the terms on either side of the equation.

Applying the same to the given equation:

$\sqrt{{(x + 7)}^{2}} = \sqrt{81}$ $sqrt((x+7)^2)=sqrt(81$

( $\sqrt{81} = \pm 9$ $sqrt81= color(blue)(+-9$ )

So,
$\sqrt{{(x + 7)}^{2}} = \pm 9$ $sqrt((x+7)^2)=color(blue)(+-9$

$(x + 7) = \pm 9$ $(x+7)=color(blue)(+-9$

Solution 1:
$x + 7 = + 9$ $x+7 = +9$
Isolating $x$ $x$ completely:
$x + 7 - 7 = + 9 - 7$ $x+7 -color(blue)(7) = +9 -color(blue)(7)$
$x = 2$ $color(blue)(x=2$

Solution 2:
$x + 7 = - 9$ $x+7 = -9$
Isolating $x$ $x$ completely:
$x + 7 - 7 = - 9 - 7$ $x+7-color(blue)(7) = -9-color(blue)(7)$
$x = - 16$ $color(blue)(x=-16$

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How do you solve this equation using the square root property ${(x + 7)}^{2} = 81$ $(x + 7)^2 = 81$ ?

1 Answer

Explanation:

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Humanities

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How do you solve this equation using the square root property (x + 7)^2 = 81(x+7)2=81(x + 7)^2 = 81?

1 Answer

Explanation:

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How do you solve this equation using the square root property ${(x + 7)}^{2} = 81$ $(x + 7)^2 = 81$ ?