The answer is: - 6 .
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Evaluate the value INSIDE the "bars".
b - a = -2 - 4 = -6 . The absolute value of the value inside inside the bars is the "positive" number of that value. The value is negative 6; so, the absolute value, or "magnitude", of "-6", is "6"; Then, then "-" (6) = -6. So the answer is: -6 .
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-99 = -9*11
176 = 16*11
Both factorizations have 11 show up. It turns out that 11 is the largest common factor.
Answer: C) 11
Note: if you divide both numerator and denominator by 11, then the fraction reduces to -9/16
Using the distributive property an equivalent expression would be 9z-54