How do you solve #(5x - 3) ^ { 2} = 49#?

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Answer 1 · 2016-11-28T05:07:22

#x = 2#
#x = -4/5#

Take the square root of both sides. This is easy in this instance, since 49 is the perfect square of 7. So:

#5x - 3 = 7#

#5x = 10#

#x = 2#

However, this is not quite the end of the problem! Remember that

#(-7)^2 = 49# as well.

Therefore,

#5x - 3 = -7# too!

#5x = -4#

#x = -4/5#