Question

using the suitable identity expand
(x+4y)^2

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Answer 1

x^2+2×4y×x+(4y)^2

x^2+8xy+16y^2

Answer 2

Answer:

$({x + 4y})^{2} \\ = {x}^{2} + 2 \times x \times 4y + ({4y})^{2} \\ = {x}^{2} + 8xy + 16 {y}^{2} \\ \\ identity = \\ ({a + b})^{2} = {a}^{2} + 2ab + {b}^{2}$