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tanak73
Nov 7, 2007, 07:33 PM
Solve the equation by using the square root property.

x^2=25

terryg752
Nov 7, 2007, 08:15 PM
What is square root of x^2?

What is square root of 25?

Equate the above.

jehan60188
Nov 10, 2007, 10:47 AM
Solve the equation by using the square root property.

x^2=25
if x^2 = k
then x = sqrt(k) or x = - sqrt(k)

so x = sqrt(25) or x = - sqrt(25)
x = 5 or x = -5

nycfunction
Nov 11, 2007, 09:53 AM
We have x^2 = 25

To solve this question, we take the square root of both sides of the equation.

When we take the square root, there are two possible answers:
a positive answer and a negative answer.

What is the square root of x^2?

In other words, since x times x = x^2, then the square root of x^2 is one of the factors or in this case x.

We type square root like this: sqrt.

What is the sqrt{25}?

What two SAME numbers when multiplied together will yield 25?

How about 5 times 5?

Yes, 5 times 5 = 25 and since we only need one of the factors, the sqrt{25} = 5.

We need a positive and a negative answer because we are dealing with square roots.

So, our final answer is x = +5 and x = -5.

Is this clear?