Like what you saw?
Create FREE Account and:
 Watch all FREE content in 21 subjects(388 videos for 23 hours)
 FREE advice on how to get better grades at school from an expert
 Attend and watch FREE live webinar on useful topics
Solving an Equation with Radicals  Problem 2
Carl Horowitz
Carl Horowitz
University of Michigan
Runs his own tutoring company
Carl taught upperlevel math in several schools and currently runs his own tutoring company. He bets that no one can beat his love for intensive outdoor activities!
Solving a equation with a radical, so the steps of solving an equation with a radical will always going to be the same. You want to isolate the radical take each side to the power to get rid of the radical you are dealing with solve for our variable, and then check your answers.
So this problem what is actually going on is we have a square root and we also have the variable again. So what’s going to end up happening is we are going to have a portion of an equation which we are going to have to factor in order to solve it.
Without getting ahead of myself let’s get to that point first. So in order to solve it we first need to isolate our radical, the square root of x is equal to x minus 2. We then want to get rid of that square root so we need to square both sides. Square root squared that just goes away leaves us with the inside and we have x minus 2².
You have to remember that we need to follow this out. Common mistake is people just want to distribute that 2 in, it’s not the same thing. So we follow this out we get x² minus 4 x plus 4. Isolate everything to one side, I always like dealing with my x² term being positive so I’m going to bring the x around if 0 is equal to x² minus 5x plus 4.
We now have a term which is a quadratic we need to factor this out, x minus 4 x minus 1 leaving us with x is equal to 4 or 1. Now with any radical equation what we are going to have to do is check your answers so we are going to plug this in to make sure they actually work.
Let’s take 4 plug it in square root of 4 is 2, 2 plus 2 is 4. So that works that’s great. Try 1 square root of 1 is 1, plus 2 is 3, 3 is not equal to 1. So what happened it we actually got a extraneous solutions one that doesn’t work which is why we have to check to make sure our answers all work. When we square each side what can happen is we can actually introduce our any answer is that isn’t going to work for this problem.
But by going through the steps for solving the equation with a quadratic we are able to get at least one answer that works.
Please enter your name.
Are you sure you want to delete this comment?
Carl Horowitz
B.S. in Mathematics University of Michigan
He knows how to make difficult math concepts easy for everyone to understand. He speaks at a steady pace and his stepbystep explanations are easy to follow.
i love you you are the best, ive spent 3 hours trying to understand probability and this is making sense now finally”
BRIGHTSTORM IS A REVOLUTION !!!”
because of you i ve got a 100/100 in my test thanks”
Get Peer Support on User Forum
Peer helping is a great way to learn. Join your peers to ask & answer questions and share ideas.
Concept (1)
Sample Problems (13)
Need help with a problem?
Watch expert teachers solve similar problems.

Solving an Equation with Radicals
Problem 1 5,014 viewsSolve:
4 ⋅ ∛x − 1 + 3 = 11 
Solving an Equation with Radicals
Problem 2 4,571 viewsSolve:
√x + 2 = x 
Solving an Equation with Radicals
Problem 3 4,248 viewsSolve:
√3x − 2 − √x + 3 = 1 
Solving an Equation with Radicals
Problem 4 588 views 
Solving an Equation with Radicals
Problem 5 521 views 
Solving an Equation with Radicals
Problem 6 490 views 
Solving an Equation with Radicals
Problem 7 484 views 
Solving an Equation with Radicals
Problem 8 522 views 
Solving an Equation with Radicals
Problem 9 563 views 
Solving an Equation with Radicals
Problem 10 519 views 
Solving an Equation with Radicals
Problem 11 540 views 
Solving an Equation with Radicals
Problem 12 456 views 
Solving an Equation with Radicals
Problem 13 505 views
Comments (0)
Please Sign in or Sign up to add your comment.
·
Delete