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How do you simplify #4sqrt5-2sqrt5#?

Answer 1

Abigail Allen

#4 sqrt5 - 2 sqrt5 = 2 sqrt5#

The question appears more difficult than it actually is.

Compare this to a question such as: 2 bags minus 4 bags equals 2 bags.

Similar terms can be used in algebra:

#4x - 2x= 2x#

#4 square - 2 square = 2 square#

In this case you can consider #sqrt5# in each term as being like terms.

#4 sqrt5 - 2 sqrt5 = 2 sqrt5#

#sqrt5# is an irrational number and cannot be written exactly, so it is better to use it like this.

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Answer 2

Isaiah Anthony

#2sqrt(5)#

#4sqrt(5)-2sqrt(5)#

these are like terms- they are both multiples of the radical #sqrt(5)#.

collecting like terms gives you #(4-2) * sqrt(5)#

#= 2 * sqrt(5)#

#=2sqrt(5)#

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Answer 3

Eva Adamson

2√5

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.