Skip to content
Systems of Equations
Example 7

Example 7: Solving Systems

Step-by-step worked example for this lesson track.

Problem

Find x in {−x−4y=25−3x−y=20\text{Find }x\text{ in }\begin{cases}-x-4y=25\\-3x-y=20\end{cases}

1. Recognize Pattern

{a1x+b1y=c1a2x+b2y=c2\begin{cases}a_1x+b_1y=c_1\\a_2x+b_2y=c_2\end{cases}

2. Apply Method

{x+2y=0−4x−2y=−24⇒(x,y)=(8,−4)\begin{cases}x+2y=0\\-4x-2y=-24\end{cases}\Rightarrow (x,y)=(8,-4)

3. Conclude

(x,y)=(−5,−5)(x,y)=(-5,-5)

Final answer

(x,y)=(−5,−5)(x,y)=(-5,-5)
Previous exampleNext exampleBack to lessonsPractice this skillTry in calculator