How to solve x'A=b' instead of Ax=b?

Question

I solve Ax=b by using

solve(A, b) 

which is faster than

solve(A) %*% b

Then, how do i solve (' is a transpose)

x'A=b'? 

I don't like to use

b' %*% solve(A) 

since this is slow. Is there any way I can solve by just one solve() function?

Answer 1

x' A = b' 

is the same as:

A' x = b

So you can basically use solve(t(A), b) and take the result's transpose to get x'.