How do you solve 4sqrtx – 7 = 13?

2 Answers
Alvin L.
Mar 11, 2018

x=25

Explanation:

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

smendyka
Mar 11, 2018

See a solution process below:

Explanation:

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

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