If 100A = 5, 10b = 2, then 2A + B=______ ．

If 100A = 5, 10b = 2, then 2A + B=______ ．

∵ 100A = 5, 10b = 2, ∵ a = lg5lg102 = 12lg5, B = LG2, ∵ 2A + B = LG2 + lg5 = 1

A ^ 2 + B ^ 2 = 100, a / 10 = B / (B + 10) solve a, B

In general, there are two unknowns and two equations, so we can consider the elimination method. Of course, if you can't think of a better method, we can get A-B = AB / 10 from a / 10 = B / (B + 10), and we can get 10000-200ab = a ^ 2 * B ^ 2 by combining this formula with a ^ 2 + B ^ 2 = 10 ^ 0. If AB is an unknown number, we can get the value of AB

What is a + B = 10. A ^ 3 + B ^ 3 = 100. A ^ 2 + B ^ 2