Algebra 1 · Reasoning with Equations & Inequalities

Identify no/infinite solution systems

Identify no/infinite solution systems.

Practice more with MathNivoAndroid app coming soonExplore the idea here, then continue practicing in the Android app when available.

What you’ll learn

Identify no/infinite solution systems.

Key idea

Equal slopes can describe either one common line or two distinct parallel lines.

Matching slopes alone cannot distinguish coincident from distinct parallel lines.

Worked example

Classify examples and non-examples for the concept 'Identify no/infinite solution systems'.

Classify the solution set of R: y=-3x+1; B: y=-3x+1. Choose with mathematical evidence.

-6-4-202466420-2-4-6CCCCCxy

Marked coordinates: C=(-2, 7); C=(-1, 4); C=(0, 1); C=(1, -2); C=(2, -5).

  1. Both slopes are -3; intercepts are 1 and 1.
  2. The equations are identical, so every point on their common line satisfies both.

Answer: infinitely many solutions — equal slopes and equal intercepts give one common line.

Quick Check

Classify examples and non-examples for the concept 'Identify no/infinite solution systems'.

Classify the solution set of R: y=-2x+0; B: y=-2x+2. Choose with mathematical evidence.

-6-4-202466420-2-4-6BRBRBRBRBRxy

Marked coordinates: B=(-2, 6); R=(-2, 4); B=(-1, 4); R=(-1, 2); B=(0, 2); R=(0, 0); B=(1, 0); R=(1, -2); B=(2, -2); R=(2, -4).

Choose one answer

Show a hint

Compare the constants after comparing the two slopes.