SOLUTION: what is the solution for 2 square root 72 plus 3 square root 50 minus square root 128

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Question 916193: what is the solution for 2 square root 72 plus 3 square root 50 minus square root 128
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
2sqrt%2872%29%2B3sqrt%2850%29-sqrt%28128%29

Think of square numbers other than 1 which are

1. factors of 72. They are 4, 9, 36. The largest is 36
2. factors of 50. There is only one, 25.
3  factors of 128. They are 4, 8, and 64.  The largest is 64

Rewrite each as a product of two numbers one of which is the
largest possible square number

2sqrt%2836%2A2%29%2B3sqrt%2825%2A2%29-sqrt%2864%2A2%29

Write each as the product of two square roots:

2sqrt%2836%29sqrt%282%29%2B3sqrt%2825%29sqrt%282%29-sqrt%2864%29sqrt%282%29%29

Take the square roots of the square numbers:

2%2A6sqrt%282%29%2B3%2A5sqrt%282%29-8sqrt%282%29

12sqrt%282%29%2B15sqrt%282%29-8sqrt%282%29

They are like terms, just like 12x%2B15x-8x=19x

Answer:  19sqrt%282%29

Edwin