Question

Tick (✓) the correct answer:
(x + 4)(x + 4) = ?
(a) (x² + 16)
(b) (x² + 4x + 16)
(c) (x² + 8x + 16)
(d) (x² + 16x)

Answer 1

(c) (x² + 8x + 16)

$$\begin{gathered} \left(x+4\right)\left(x+4\right) \\ \Rightarrow {\left(x+4\right)}^2(\mathrm{according}\mathrm{to}\mathrm{the}\mathrm{formula}{\left(a+b\right)}^2=a^2+2ab+b^2) \\ \Rightarrow \left(x^2\right)+2\left(x\right)\left(4\right)+{\left(4\right)}^2 \\ \Rightarrow x^2+8x+16 \end{gathered}$$