ACT Preparation / Unit 9 ACT 0825 short lesson, about 20 seconds
One, None or Infinitely Many
Captions available
The idea
Different slopes: one solution. Same slope, different intercepts: parallel lines, no solution, and solving gives a false statement like 0 = 5. The same line twice: infinitely many, and an identity like 0 = 0.
In practice
y = 2x + 1 and y = 2x − 3 share a slope and differ in intercept, so there is no solution.
Where people slip
Compare the slopes first.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Unlocks
- Nothing yet depends on this.
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