What is the difference of 5[radical 7] and 3[radical 28]?

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Answer 1 · 2016-08-09T13:18:29

#sqrt(7)#

Assumption: The question is asking #|color(white)(./.)5sqrt(7)-3sqrt(28)color(white)(./.)|#

Note that the two vertical lines represent an 'absolute' value. This means that no matter if what is inside the | | the outcome is always positive

Note that #4xx7=28 -> 2^2xx7=28#

Write the question as: #5sqrt(7)-3sqrt(2^2xx7)#

Take the #2^2# outside the square root

#|color(white)(./.)5sqrt(7)-(3xx2)sqrt(7)color(white)(./.)|" " ->" "|color(white)(./.)5sqrt(7)-6sqrt(7)color(white)(./.)|#

#|color(white)(./.)-sqrt(7)color(white)(./.)| = +sqrt(7)#