Question

For what values of a is the sum of the fractions 2a−1/4 and a−1/3 positive?

Answer 1

$\left(2a-\dfrac{1}{4}\right)+\left(a-\dfrac{1}{3}\right) > 0\\\\(2a+a)-\dfrac{1}{4}-\dfrac{1}{3} > 0\\\\3a-\dfrac{1}{4}-\dfrac{1}{3} > 0\qquad|\cdot12\\\\12(3a)-12\left(\dfrac{1}{4}\right)-12\left(\dfrac{1}{3}\right) > 0\\\\36a-3-4 > 0\\\\36a-7 > 0\qquad|+7\\\\36a > 7\qquad|:36\\\\a > \dfrac{7}{36}$