Finding Side Length AC in a Deltoid with Area 72 cm² and MD = 3 cm

To solve for the length of $AC$ in the deltoid:

• Given $MD = 3$ cm, which implies $BD = 2 \times MD = 6$ cm.
• The area of the deltoid is given by the formula: $\text{Area} = \frac{1}{2} \times AC \times BD$.

Putting the known values into the formula:
$72 = \frac{1}{2} \times AC \times 6$.

To isolate $AC$, multiply both sides by 2:

$144 = AC \times 6$.

Divide both sides by 6 to solve for $AC$:

$AC = \frac{144}{6} = 24 \, \text{cm}$.

Therefore, the length of the side $AC$ is $24 \, \text{cm}$.