Question Number 36691 by Tinkutara last updated on 04/Jun/18
Commented by Rasheed.Sindhi last updated on 05/Jun/18
$${ax}+{cy}+{bz}={X},{cx}+{by}+{az}={Y},{bx}+{ay}+{cz}={Z} \\ $$$$\mathrm{Adding}\:\mathrm{the}\:\mathrm{three}: \\ $$$$\left({a}+{b}+{c}\right)\left({x}+{y}+{z}\right)={X}+{Y}+{Z} \\ $$$$…… \\ $$$$…. \\ $$
Commented by Tinkutara last updated on 08/Jun/18
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