Answer: B and E are irrational numbers
Simplifying
12x + 10 + 3 + 8x = 0
Reorder the terms:
10 + 3 + 12x + 8x = 0
Combine like terms: 10 + 3 = 13
13 + 12x + 8x = 0
Combine like terms: 12x + 8x = 20x
13 + 20x = 0
Solving
13 + 20x = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-13' to each side of the equation.
13 + -13 + 20x = 0 + -13
Combine like terms: 13 + -13 = 0
0 + 20x = 0 + -13
20x = 0 + -13
Combine like terms: 0 + -13 = -13
20x = -13
Divide each side by '20'.
x = -0.65
Simplifying
x = -0.65
F(x)/g(x) = (2x +3)(x -1)/(x -1) = 2x +3 . . . . . x ≠ 1
The domain of (f/g)(x) is all real numbers except 1.
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The domain of any rational function necessarilly excludes any values that make the function undefined, that is, that make the denominator zero.
Mean is equal to sum/ number of values
27+3+2+25+5=62
62/5=12.4
Final answer: D, 12.4 years