Question

expand (3a-4b-3c) the whole square

Answer 1

$\textbf{ \huge{ Hello Mate! }}$

$= {(3a - 4b - 3c)}^{2}$

Common questions?

We know that in formula,

${(x + y + z)}^{2} \\ = {x}^{2} + {y}^{2} + {z}^{2} + 2(xy + yz + zx)$

All units are in + ve. But what to do here? Because two units are in minus. See what we can do to match it according to our formula.

$= {(3a + (- 4b) + ( - 3c))}^{2} \\ = {(3a)}^{2} + {( - 4b)}^{2} + {( - 3c)}^{2} + 2((3a)( - 4b) + ( - 4b)( - 3c) + ( - 3c)(3a)) \\ = 9 {a}^{2} + 16 {b}^{2} + 9 {c}^{2} + 2( - 12ab + 12bc - 9ca) \\ = 9 {a}^{2} + 16 {b}^{2} + 9 {c}^{2} - 24ab + 24bc - 18ca$

Hope I was successful in not only reaching to answer but also in explaining you.

$\textbf{ Have great future ahead! }$