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## Comment on

x/2 and so on## Hey Brent!

This is a good example of when your idea of "something" comes handy.

As soon as I got x^2 + 4x + 2 = 0, I simply said "something + 2 = 0, which means "something" + 5 has to = 3.

## Awesome solution - well done!

Awesome solution - well done!

For others reading this, here's the video on the Something Method: https://www.gmatprepnow.com/module/gmat-algebra-and-equation-solving/vid...

## Hi Brent,

Could you explain how we can use the something method here. I've seen the video related to this topic but still a bit rusty.

Thanks,

## When we cross multiply the

When we cross multiply the original equation, we get: x² + 10x = 6x - 2

Rearrange to get: x² + 4x + 2 = 0

Our goal is to find the value of x² + 4x + 5

abrahamic01 thought of this as something + 5

abrahamic01 noted that we can think of x² + 4x + 2 = 0 as something + 2 = 0

So, to get "something + 5", we need to take the equation "something + 2 = 0" and add 3 to both sides to get: "something + 5 = 3"

In other words, " x² + 4x + 5 = 3"

## For this question, I cross

Then, plugging in these two potential solutions showed me that x=-2 yielded one of the answer choices, so that answer choice ( B) must be the solution.

Where did I go wrong?

## Without seeing your steps, it

Without seeing your steps, it's hard to tell what happened.

In the video solution, I also cross multiplied the given equation.

When I did so, I got the equation: x² + 4x + 2 = 0

The left side of this equation cannot be factored, so I'm not sure how you got the solutions x = -2 and x = -6

That said, your strategy is correct; you just made an error at some point after you cross multiplied.

## Hi Brent, I have a question

If we have x² + 4X + 2, it means that we have (x+2)². So x=-2.

If we substitute x = -2 to x² + 4X + 5, we have --> 4 - 8 + 5 --> = 1.

So, I understood the other method but I first tried this one, and in this case, the solution should be B. Can you help me?

## There are a few problems with

There are a few problems with your solution.

To begin, x² + 4x + 2 doesn't factor to equal (x + 2)²

Instead, x² + 4x + 4 = (x + 2)²

Also, x² + 4x + 2 isn't an equation; it's an expression that has infinitely many values, depending on the value of x.

Since x² + 4x + 2 isn't that equation, it can't be solved.

So, even if the question provided the expression x² + 4x + 4, there's still no way to solve it, because it's not an equation.

On the other hand, if we have the equation x² + 4x + 4 = 0, then we can factor the left side to get: (x + 2)(x + 2) = 0, in which case the solution is x = -2

Does that help?

## Hello Brent, you are totally