Chapter 8 - Systems of Linear Equations and Problem Solving - 8.2 Solving by Substitution or Elimination - 8.2 Exercise Set - Page 516: 16

$(2,-7)$

Isolate $n$ in eq.$2$ $ 4m+n=1\qquad$ ... subtract $4m$ $n=1-4m\qquad $(*) Replace $n$ with $1-4m$ in the other equation: $ m-2(1-4m)=16\qquad$ ... and solve for $x$. Simplify $m-2+8m=16$ $ 9m-2=16\qquad$ ... add $2$ $ 9m=18\qquad$ ... divide with $9$ $m=2$ Now, back-substitute into (*) $n=1-4(2)=1-8=-7$ Form an ordered pair $(m,n) $ as the solution to the system $(2,-7)$