We give a classical algorithm for linear regression analogous to the quantum matrix inversion [Harrow, Hassidim, and Lloyd, Physical Review Letters'09, arXiv:0811.3171] low-rank matrices [Wossnig, Zhao, Prakash, Letters'18, arXiv:1704.06174], when input $A$ is stored in data structure applicable QRAM-based state preparation. Namely, suppose we are given an $A \in \mathbb{C}^{m\times n}$ with mi...