SOLUTION: combine the radicals below. show your steps. 11. 4 and square root of 11 + 8 and square root of 11 12. square root of 80 - square root of 5 please help me!!!

Algebra ->  Problems-with-consecutive-odd-even-integers -> SOLUTION: combine the radicals below. show your steps. 11. 4 and square root of 11 + 8 and square root of 11 12. square root of 80 - square root of 5 please help me!!!      Log On


   

Question 252922: combine the radicals below. show your steps.

11. 4 and square root of 11 + 8 and square root of 11
12. square root of 80 - square root of 5
please help me!!!
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
combine the radicals below. show your steps.
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11. 4 and square root of 11 + 8 and square root of 11
I think you mean
4%2Asqrt%2811%29+%2B+8%2Asqrt%2811%29
Think of sqrt(11) as X.
4X+%2B+8X+=+12X
So, we get
12sqrt%2811%29
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12. square root of 80 - square root of 5
sqrt%2880%29+-+sqrt%285%29
sqrt%2880%29+=+sqrt%285%2A16%29 = sqrt%2816%29%2Asqrt%285%29+=+4%2Asqrt%285%29
So, 4*sqrt(5) - sqrt(5) = 3sqrt(5)