Answer:

4. C. 3x² - 12 = 5x

5. A. 3

Solution:

4.

Let the original number be x.

12 subtracted from ( 3 times the square of a positive number ) would be 3x² - 12

5 times the number is 5x

Therefore the answer for number 4 is C, 3x² - 12 = 5x

5.

The option 5 can be excluded as 12 is not a multiple of 5.

if x is 3:

3 × 9 - 12 = 5 × 3

15 = 15, which is true

If x is 4:

3 × 16 - 12 = 5 × 4

36 = 20, which isn't true.

if x is 6:

3 × 36 - 12 = 5 × 6

96 = 30, which also isn't true.

So the answer for number 5 is A, 3