Final answer:
To find the length of MP, write and solve an equation using the given expressions for MN and NP. The length of MP is 12 units.
Step-by-step explanation:
Mathematics:
To find the length of MP, we need to find the values of x and substitute them into the given expressions. Since N is the midpoint of MP, MN and NP are equal in length. Therefore, x + 8 = 4x - 4. Simplifying this equation, we get 3x = 12, which means x = 4. Substituting x = 4 into MN, we find that MN = 4 + 8 = 12. Substituting x = 4 into NP, we find that NP = 4(4) - 4 = 12. Since MN and NP are equal, MP has a length of 12 units. Therefore, the correct answer is (A) 12.