Question 362688
a = 2g-6,
5a = 8g.
Then, by substitution, 5(2g-6) = 8g,
10g-30 = 8g,
10g-8g = 30,
2g = 30,
g = 15.  A grammar book weighs 15 ounces, an algebra book, 2*15 - 6 = 24 ounces.