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If 2ˣ⁺²=8⁻ˣ⁺⁸, then x equals
a. 4.8
b. 6
c. 5.5
d. 4.4

1 Answer

5 votes

Final answer:

To solve the equation 2^(x+2) = 8^(-x+8), the base 8 is expressed as 2^3, resulting in an equation with a common base. The exponents are then equated and solved for x, yielding the solution x = 5.5.

The correct answer is c. 5.5.

Step-by-step explanation:

To solve the exponential equation 2x+2 = 8-x+8, we must recognize that 8 is a power of 2, since 8 = 23. Therefore, we can rewrite the equation with a common base:

2x+2 = (23)-x+8

Now apply the power rule (am)n = amn, which gives:

2x+2 = 2-3x+24

Since the bases are the same, we can equate the exponents:

x + 2 = -3x + 24

Now, solve for x:

4x = 22

x = 22 / 4

x = 5.5

Therefore, the correct answer is c. 5.5.

User Chris McKelt
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