How do you solve # 4sqrtx – 7 = 13#?

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Answer 1 · 2018-03-11T11:54:22

#x=25#

Add #7# to both sides:

#4sqrtx-cancel(7+7)=13+7#

#4sqrtx=20#

Divide both sides by #4#:

#(cancel4sqrtx)/cancel4=20/4#

#sqrtx=5#

Square both sides:

#(sqrtx)^2=5^2#

#x=25#

Answer 2 · 2018-03-11T11:54:35

See a solution process below:

First, add #color(red)(7)# to each side of the equation to isolate the #x# term while keeping the equation balanced:

#4sqrt(x) - 7 + color(red)(7) = 13 + color(red)(7)#

#4sqrt(x) - 0 = 20#

#4sqrt(x) = 20#

Next, divide each side of the equation by #color(red)(4)# to isolate the radical while keeping the equation balanced:

#(4sqrt(x))/color(red)(4) = 20/color(red)(4)#

#(color(red)(cancel(color(black)(4)))sqrt(x))/cancel(color(red)(4)) = 5#

#sqrt(x) = 5#

Now, square both sides of the equation to solve for #x# while keeping the equation balanced:

#(sqrt(x))^2 = 5^2#

#x = 25#