How do you solve #\sqrt { 2x + 7} = 7#?

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Answer 1 · 2017-06-12T00:46:07

#x=21#

Let's start with the original problem:

#sqrt(2x+7)=7#

Since there's a square root sign on the left side and it is rather bothersome, we can square both sides of the equation to get rid of it:

#sqrt(2x+7) ^2=7^2#

#2x+7=49#

Now, we can subtract #7# on both sides to isolate #x#:

#2x=42#

And now we divide both sides by #2# to find the answer:

#(color(red)(cancel(color(black)(2)))x)/cancel(color(red)(2))=42/2#

#x=21#