Solve for rrr: \dfrac{7}{10}=r-\left(-\dfrac{8}{5}\right) 10 7 ​ =r−(− 5 8 ​ )start fraction, 7, divided by, 10, end fraction, equals, r, minus, left parenthesis, minus, start fraction, 8, divided by, 5, end fraction, right parenthesis r =r=r, equals