2018 · Q2
If a + b = 2c, then what is the value of a/(a - c) + c/(b - c)?
Elementary MathematicsAlgebra
- A-1
- B0
- C1
- D2
Explanation
From a + b = 2c we get a − c = c − b. Rewrite the second fraction with denominator (a − c): c/(b − c) = −c/(a − c). The sum becomes a/(a − c) − c/(a − c) = (a − c)/(a − c) = 1. The keyed answer is (C).