# Solving an Equation w/ Radical

• Sep 16th 2009, 12:44 PM
Giulie
We just finished up studying quadratic formulas and have now moved onto solving other types of equations. I need some help with some problems. Here are the first few
(this sign √ = square root symbol) :

1. 3√1-X=-2 (the square root is over the entire equation of 1-X)

2. √8-2x=2x-2 (square root is over entire equation of 8-2x)

• Sep 16th 2009, 01:16 PM
e^(i*pi)
Quote:

Originally Posted by Giulie
We just finished up studying quadratic formulas and have now moved onto solving other types of equations. I need some help with some problems. Here are the first few
(this sign √ = square root symbol) :

1. 3√1-X=-2 (the square root is over the entire equation of 1-X)

2. √8-2x=2x-2 (square root is over entire equation of 8-2x)

1. $3\sqrt{1-x} = -2$

Square both sides: $3^2(\sqrt{1-x})^2 = 4$

$1-x = \frac{4}{9}$

$x = \frac{5}{9}$
• Sep 16th 2009, 01:34 PM
Krizalid
Quote:

Originally Posted by e^(i*pi)

1. $3\sqrt{1-x} = -2$

no solution, range of $f(x)=\sqrt x$ is $\mathbb R_0^+.$
• Sep 16th 2009, 02:14 PM
Giulie
thanks!
Okay,

and so for the second problem I end up getting 4x(to the second power)-6x-4=0...and because that doesn't factor out is the right move to plug it into the quadratic formula (equation) ?