Question

What is the solution when 9x+6y=-3 x+8y=29

Answer 1

We have
$9x + 6y = - 3 - - - (1)$
and

$x + 8y = 29$
$\rightarrow \: x = 29 - 8y - - - (2)$


Using elimination will be faster, so plug in equation (2) in equation (1)

$9(29 - 8y) + 6y = - 3$

Expand brackets, we obtain,

$261-72y+6y=-3$
Simplifying gives,

$-66y=-264$

$y = \frac{ - 264}{ - 66} = 4$
$x = 29 - 8(4) = - 3$