Which of the following is equivalent to √45−√5 ?

The answer you are looking for is 2√5, which is the same thing as √20.

Solution/Explanation:

Writing out the problem first

√45-√5

Testing different values to try to get the square root to be 5

Testing 2:

Take 2

Square it

2²=4

Divide 45 by 4

Nope, this will not work. It will not have a √5, and the base will not be a whole number. Now, let's try 3.

Take 3

Square it

3²=9

Divide 45 by 9, which is 5. For extra checking, you can multiply 9 by 5, which is 45, just to make sure that you calculated everything correctly.

Three works. So, now, we can have 3 as the base and 5 as the square root.

So, now, we can formulate a more simplified problem:

3√5-√5

To make it more easy to simplify more, we can write it out like this:

3√5-1√5

Subtract the bases 3 and 1. You will get 2. The √5 will remain the same.

2√5

So, therefore, the final answer to this problem is 2√5.

Hope this helped answer your question for you. Good day to you.

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0