5) \( \left\{\begin{array}{l}y=-0.5 x-5 \\ y=0.9 x+9\end{array}\right. \)

Solve the system of equations \( y=-0.5x-5;y=0.9x+9 \). Solve the system of equations by following steps: - step0: Solve using the substitution method: \(\left\{ \begin{array}{l}y=-0.5x-5\\y=0.9x+9\end{array}\right.\) - step1: Substitute the value of \(y:\) \(-0.5x-5=0.9x+9\) - step2: Move the expression to the left side: \(-0.5x-0.9x=9+5\) - step3: Add and subtract: \(-1.4x=9+5\) - step4: Add and subtract: \(-1.4x=14\) - step5: Change the signs: \(1.4x=-14\) - step6: Divide both sides: \(\frac{1.4x}{1.4}=\frac{-14}{1.4}\) - step7: Divide the numbers: \(x=-10\) - step8: Substitute the value of \(x:\) \(y=-0.5\left(-10\right)-5\) - step9: Simplify: \(y=0\) - step10: Calculate: \(\left\{ \begin{array}{l}x=-10\\y=0\end{array}\right.\) - step11: Check the solution: \(\left\{ \begin{array}{l}x=-10\\y=0\end{array}\right.\) - step12: Rewrite: \(\left(x,y\right) = \left(-10,0\right)\) The solution to the system of equations is \( (x, y) = (-10, 0) \).