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

1 Answer
Aug 13, 2015

Answer:

The solutions are
#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#

(#sqrt81= color(blue)(+-9#)

So,
#sqrt((x+7)^2)=color(blue)(+-9#

#(x+7)=color(blue)(+-9#

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

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