Question

Identify the expression equivalent to 2x + 8 by substituting x = 7 and x=5.

A, 2x + 10 + 10
B. 2(x+2)
C. (x + 4) + (x + 4)
D. (x + 4)
E. 2(2x + 4)

Answer 1

The expression equivalent to 2x + 8, after substituting x=7 and x=5, is found to be Option C, which is (x + 4) + (x + 4).

Step-by-step explanation:

To identify the expression equivalent to 2x + 8, let's consider each of the given options by substituting the values of x as 7 and 5:

• Substituting x = 7 into 2x + 8:
  2(7) + 8 = 14 + 8 = 22.
• Substituting x = 5 into 2x + 8:
  2(5) + 8 = 10 + 8 = 18.

Now let's test each option:

1. Option A, 2x + 10 + 10, is not equivalent as it adds 20 to 2x instead of 8.
2. Option B, 2(x+2), when expanded is 2x + 4, which is also not equivalent.
3. Option C, (x + 4) + (x + 4), simplifies to 2x + 8, which matches the expression we are trying to find the equivalent of.
4. Option D, (x + 4), is just half of the correct expression.
5. Option E, 2(2x + 4), expands to 4x + 8, which is also not equivalent to 2x + 8.

Therefore, the expression equivalent to 2x + 8 is Option C, (x + 4) + (x + 4).