Question

1. $6c - 9d = 111$

$5c - 9d = 103$

Explanation:

Step1: Subtract equations to eliminate $9d$

$(6c - 9d) - (5c - 9d) = 111 - 103$

Step2: Simplify to solve for $c$

$6c - 9d -5c +9d = 8$
$c = 8$

Step3: Substitute $c=8$ into second equation

$5(8) - 9d = 103$

Step4: Solve for $d$

$40 - 9d = 103$
$-9d = 103 - 40$
$-9d = 63$
$d = \frac{63}{-9} = -7$

Answer:

$c=8$, $d=-7$