How do you solve 4x - (x * 3^(1/2)) = 6?

1 Answer
Oct 13, 2015

x = 6/13 * (4 + sqrt(3))

Explanation:

The idea hee is to isolate x on one side of the equation.

To do that, start by using x as a common factor for the expression that's on the left-hand side of the equation

4x - x * 3^(1/2) = 6

x * (4 - 3^(1/2)) = 6

You can rewrite the equation by replacing the fractional exponent by its corresponding radical term

x * (4 -sqrt(3)) = 6

DIvide both sides of the equation by (4 - sqrt(3)) to isolate x on the left-hand side of the equation

( x* color(red)(cancel(color(black)(4-sqrt(3)))))/(color(red)(cancel(color(black)(4-sqrt(3))))) = 6/(4 -sqrt(3))

x = 6/(4 - sqrt(3))

Rationalize the denominator of the fraction by multiplying it by 1 = (4 + sqrt(3))/(4 + sqrt(3)). The expression (4 + sqrt(3)) is the conjugate of (4 - sqrt(3)). The fraction will thus be equivalent to

6/(4 - sqrt(3)) * (4 + sqrt(3))/(4 + sqrt(3)) = (6 * (4 + sqrt(3)))/((4 - sqrt(3))(4 + sqrt(3))

= (6 * (4 + sqrt(3)))/(4^2 - (sqrt(3))^2)

= 6/13 * (4 + sqrt(3))

Therefore, x will be equal to

x = color(green)(6/13 * (4 + sqrt(3)))