Square and cube binomials Practice Questions (Grade 9)

Question 1easy

Which expression is equivalent to $(x - 4)^{2}$ ?

$(x - 4)^{2} = x^{2} - 2(x)(4) + 4^{2} = x^{2} - 8x + 16$ .

Question 2easy

Which expression is equivalent to $(2x + 1)^{2}$ ?

$(2x + 1)^{2} = (2x)^{2} + 2(2x)(1) + 1^{2} = 4x^{2} + 4x + 1$ .

Question 3easy

Which expression is equivalent to $(x + 5)^{2}$ ?

$(x + 5)^{2} = x^{2} + 2(x)(5) + 5^{2} = x^{2} + 10x + 25$ .

Question 4easy

Which expression is equivalent to $(3x - 2)^{2}$ ?

$(3x - 2)^{2} = (3x)^{2} - 2(3x)(2) + 2^{2} = 9x^{2} - 12x + 4$ .

Question 5easy

Which expression is equivalent to $(x - 1)^{3}$ ?

$(a - b)^{3} = a^{3} - 3a^{2}b + 3ab^{2} - b^{3}$ ; with $a = x$ and $b = 1$ , this gives $x^{3} - 3x^{2} + 3x - 1$ .

Question 6easy

Which expression is equivalent to $(2x - 1)^{3}$ ?

$(a - b)^{3} = a^{3} - 3a^{2}b + 3ab^{2} - b^{3}$ ; with $a = 2x$ and $b = 1$ , this gives $8x^{3} - 12x^{2} + 6x - 1$ .

Question 7easy

Which expression is equivalent to $(x + 3)^{3}$ ?

$(a + b)^{3} = a^{3} + 3a^{2}b + 3ab^{2} + b^{3}$ ; with $a = x$ and $b = 3$ , this gives $x^{3} + 9x^{2} + 27x + 27$ .

Question 8easy

Which expression is equivalent to $(2x + 1)^{3}$ ?

$(a + b)^{3} = a^{3} + 3a^{2}b + 3ab^{2} + b^{3}$ ; with $a = 2x$ and $b = 1$ , this gives $8x^{3} + 12x^{2} + 6x + 1$ .

Square and cube binomials practice