Subtracting and Adding Irrational Numbers

Only _____________________________ can be combined when adding and subtracting radicals.

• Like radical expressions

• Unlike radical expressions

• radicals with the same index

• radicals with different indexes.

Subtract: 2√18 - 3√8

• 0

• 3√2

• √2

• -4√2

• 
• 
• 
• 

If x = √7 and y = √11, what is the value of x - y?

• √(7 - 11)

• x + y

• x - y = √7 - √11

• √(11 - 7)

Perform the operation.  Express your answer in simplest form.

• 4√47

• -4√47

• 1

• 16√6  -  15√5

Simplify

3√2 - 3√18

• -4√8

• 4√9-6√3

• 5√12

• -6√2

Simplify completely.

• -1

• -√5

• -6√5

• -30

2√3 + 4√2 - √2 + √3

• 4√2 - 3√3

• 3√3 + 3√2

• 6√5

• 5√6

13√2 - 4√2

• 9

• 2√9

• 9√2

• 9√20

You cannot add or subtract radical expression if they have different indices and the same radicand. 

• TRUE

• FALSE