Question

Find the co-ordinates of the point of intersection of two lines.

$2x-7y=2$

$4x+5y=42$

Answer 1

Given equation, $2x-7y=2$ ……..(i)

$4x+5y=42$ ………(ii)

Multiply (i) by $2$ and subtracting (ii),

$4x-14y=21$

$4x+5y=42$

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___________

$-19y=-38$

___________

$y=2$

Substituting $y=2$ in (i)

we get $x=\frac{2+7\times 2}{2}=8$.