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If $$a-6b+6c=4$$ and $$6a+3b-3c=50$$, where a, b and c are real numbers, the value of $$2a+3b-3c$$ is
Given, $$a-6b+6c=4$$ --->(1)
and, $$6a+3b-3c=50$$ ---->(2)
Multiplying eqn (1) with $$x$$, $$ax-6bx+6cx=4x$$
And multiplying eqn (2) with $$y$$, $$6ay+3by-3cy=50y$$
So, $$x+6y=2$$ and $$3y-6x=3$$
So, $$x+6y=2$$ ---->(3) and $$-2x+y=1$$ ---->(4)
Multiplying eqn (4) with 6 and subtracting from eqn (3),
$$13x=-4$$
So, $$x=-\dfrac{4}{13}$$
Putting the value of $$x$$ in equation (4),
$$y=\dfrac{5}{13}$$
So, the final answer is $$4x+5y$$
=$$4\left(-\frac{4}{13}\right)+50\left(\frac{5}{13}\right)=-\frac{16}{13}+\frac{250}{13}=\frac{234}{13}=18$$
So, correct answer is $$18$$.
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