Fill in the blank to make the trinomial a perfect square trinomial. $4 x ^ { 2 } - \underline { ( \quad ) } + 9$

A) $4 x^{2}-\underline{(26 x)}+9$
B) $4 x ^ { 2 } -\underline{(6 x)}+ 9$
C) $4 x ^ { 2 } - \underline{(24 x)} + 9$
D) $4 x ^ { 2 } - \underline{(12 x)} + 9$

Question

Fill in the blank to make the trinomial a perfect square trinomial. $4 x ^ { 2 } -  \underline { (  \quad  ) } + 9$

A) $4 x^{2}-\underline{(26 x)}+9$
B) $4 x ^ { 2 } -\underline{(6 x)}+ 9$
C) $4 x ^ { 2 } - \underline{(24 x)} + 9$
D) $4 x ^ { 2 } - \underline{(12 x)} + 9$

Quizplus · Accepted Answer

A perfect square trinomial takes the form $(ax)^2 - 2abx + b^2$. Here, $a = 2$ and $b = 3$, so $2ab = 2 \times 2 \times 3 = 12$. Thus, the correct choice is $4x^2 - 12x + 9$.

Fill in the Blank to Make the Trinomial a Perfect 4x2−()‾+94 x ^ { 2 } - \underline { ( \quad ) } + 94x2−()​+9

Fill in the Blank to Make the Trinomial a Perfect $4 x ^ { 2 } - \underline { ( \quad ) } + 9$