Calculate the Area of a Deltoid with Diagonals 7 and 10 Units

To solve this problem, we need to calculate the area of the deltoid using the formula for the area in terms of diagonals:

• Identify the two diagonals: $AC = 10$ cm and $BD = 7$ cm.
• Use the formula for the area of a deltoid: $A = \frac{1}{2} \times d_1 \times d_2$.
• Substitute the values of the diagonals into the formula: $A = \frac{1}{2} \times 10 \times 7 = \frac{70}{2} = 35$.

Thus, the area of the deltoid is $\textbf{35 cm}^2$.

Therefore, the solution to the problem is $\textbf{35 cm}^2$, which corresponds to choice 3.