Posted by Bob on .
Help Please?
1.30√25 x 8√49
2. 6√64 + 12√36
3. 4√13  6√13

Algebra2 
Reiny,
30√25 x 8√49
= 30√25√1 x 8√49√1
=150√1 x 56√1
= 8400 (1)
= 8400 , remember that √1 x √1 = i x i = i^2 = 1
do the others the same way, let me know what you got 
Algebra2 
Bob,
I'm Doing Problem 2 Right Now .
But I'm Stuck How Did You Get 150 In the 3rd Line? 
Algebra2 
Reiny,
30√25√1 x 8√49√1
= 30 x 5 x √1 x 8 x 7 x √1
= 150 x √1 x 56 x √1
= 8400 x i^2
= .... 
Algebra2 
Sara,
Oh Okay .
I Tried The Other Two Problems.
For #1 I Got 120 As My Answer.
For #2 I Got 37 As My Answer. 
Algebra2  Sara 
Steve,
Nope:
6√64 + 12√36 = 6*8i + 12*6i = 120i
4√13  6√13 = (46)√13 = 2√13 i