If the perimeter of a triangle is 12, which of the following could be the length of one side of the triangle?

a. 8
b. 7
c. 6
d. 5

Would the correct answer be d. 5?

And how do you go about answering this type of question? I just guessed; I figured it was the smallest number.. and 8 was too long to be a side.

You did it correctly. you look at the other two sides, they have to be greater than the side given. If a is a side, then b+c must be greater than a.

To find the possible length of one side of the triangle given its perimeter, you can use the fact that the sum of the lengths of any two sides of a triangle must be greater than the length of the remaining side.

In this case, the perimeter of the triangle is 12. Let's consider each option and see if it satisfies the condition:

a. 8: The sum of two sides must be greater than 8. Since the perimeter is only 12, it is not possible for the other two sides to add up to 8. Therefore, 8 is not a possible length.

b. 7: The sum of two sides must be greater than 7. Since the perimeter is only 12, it is not possible for the other two sides to add up to 7. Therefore, 7 is not a possible length.

c. 6: The sum of two sides must be greater than 6. Since the perimeter is only 12, it is not possible for the other two sides to add up to 6. Therefore, 6 is not a possible length.

d. 5: The sum of two sides must be greater than 5. For example, if the other two sides are both 4, then the sum is 4 + 4 = 8, which is greater than 5. Therefore, 5 is a possible length.

From the options provided, the correct answer would indeed be d. 5.

Now, to approach this type of question systematically without guessing, you can consider the condition mentioned earlier (sum of two sides must be greater than the length of the remaining side) and apply it to each option. This helps eliminate the options that do not satisfy the condition and narrow down the possibilities.