Final answer:
Julie and Samuel used a Direct Proof to prove m/cbd = 65.
Step-by-step explanation:
To prove m/cbd = 65, Julie and Samuel used a Direct Proof. In a direct proof, you start with the given information and use logical reasoning, properties, and previously proven theorems to arrive at the desired conclusion. Julie and Samuel probably used properties of ratios and division, and the information given about m and cbd, to show that m divided by cbd is equal to 65.