SOLUTION: square root of 80 - square root of 45

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Question 447668: square root of 80 - square root of 45
Answer by Leaf W.(135) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%2880%29+-+sqrt%2845%29
First, factor the numbers within the square root signs.
sqrt%282%2A2%2A2%2A2%2A5%29+-+sqrt%283%2A3%2A5%29
Every pair of identical numbers within the square root sign equals one of the same number outside of the square root sign. For example, sqrt%282%2A2%29+=+2. In the first square root, you have two pairs of two, so you can pull out two twos. In the second square root, you have one pair of three, so you can pull out one three: 2%2A2%28sqrt%285%29%29+-+3%28sqrt%285%29%29
You can simplify 2*2 by multiplying: 4%28sqrt%285%29%29+-+3%28sqrt%285%29%29
Now, you have two "like terms" because they have the same number within the square root sign. You can now subtract them like you would with variables (4x - 3x = x): 1%28sqrt%285%29%29, or sqrt%285%29
Therefore, sqrt%2880%29+-+sqrt%2845%29+=+sqrt%285%29