Solve the Equation: Finding Missing Factors in 40-?×?=40

To solve this problem, we'll follow these steps:

• Step 1: Recognize that for the equation $40 - ? \times ? = 40$ to remain true, the term $? \times ?$ must equal zero.
• Step 2: Use the property of multiplication by zero to identify the values of $?$.
• Step 3: Check each pair from the given choices against this requirement.

Now, let's evaluate each choice:

• Choice (1): $4, -5$ results in $4 \times -5 = -20$, thus $40 - (-20) = 60$. Does not satisfy the equation.
• Choice (2): $6, 3$ results in $6 \times 3 = 18$, thus $40 - 18 = 22$. Does not satisfy the equation.
• Choice (3): $0, 3$ results in $0 \times 3 = 0$, thus $40 - 0 = 40$. Satisfies the equation.
• Choice (4): $1, 20$ results in $1 \times 20 = 20$, thus $40 - 20 = 20$. Does not satisfy the equation.

Hence, the correct choice is the pair $0, 3$ as it satisfies the condition required by the equation.

Therefore, the missing values are $0, 3$.