Question

Please explain how to solve:
$(0.4m-0.3n)^{2}+(0.4m-0.3n)^{2}$

Answer 1

$\sf{(0.4m-0.3n)^{2}+(0.4m-0.3n)^{2}} \\ \\ \sf{ \implies{ {(0.4m)}^{2} + {(0.3n)}^{2} - 2 \times 0.4m \times 0.3n + {(0.4m)}^{2} }} \\ \\ \sf{ \implies{ + \: {(0.3n)}^{2} + 2 \times 0.4m \times 0.3n }} \\ \\ \sf{\implies{ {(0.4m)}^{2} + {(0.3n)}^{2} + {(0.4m)}^{2} + {(0.3n)}^{2} }} \\ \\ u \sf{ \implies{2 \times ({(0.4m)}^{2} + {(0.3n)}^{2})}} \\ \\ \sf{ \implies{2 \times ( {1.6m}^{2} + {0.9n}^{2} }} \\ \\ \sf{ \implies{3.2 {m}^{2} + {1.8n}^{2} }} ....... [ A ]$

$\sf{ \bold{ Additional \: Identities \: - }} \\ \\ \sf{ {( a - b ) }^2 = a^2 + b^2 - 2 ab } \\ \\ { {( a -+b ) }^2 = a^2 + b^2 + 2 ab } \\ \\ \sf{ (a+b)(a-b) = a^2 - b^2 }$

Answer 2

Step-by-step explanation:

above person is right..