Difference of Square 1/12/18

If x=4 then what is x² ?

• 8
• 16
• 4
• 42

What is the square root of  36?

• 6
• 8
• 18
• 12

What is the GCF for this expression:
 25x²  − 50

• 5
• 25
• 15
• 10

What is the GCF for this expression?
9x² + 18

• 3
• 6
• 9
• 18

Factor completely:
b² − 1

• (b²−1)(b² + 1)
• (b−1)(b−1)
• (b−1)(b+1)
• (b+1)(b+1)

Factor completely:
4x²−9

• (2x−3)(2x−3)
• (4x-9)(4x+9)
• (4x−3)(4x+3)
• (2x−3)(2x+3)