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Linear equationsAlgebraMiddle schoolabout 1:07

Solve -3(x + 1) = 8x + 2: animated lesson

A narrated, step-by-step linear equations video lesson with captions. Final answer: x = -5/11 ≈ -0.45454545.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.4 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Solving an equation
$-3~\left( x+1\right) = 8~ x+2$
2. Steps, part 1
1. $-3~\left( x+1\right) = 8~ x+2$
  Start with the equation
2. $-3x - 3 = 8x + 2$
  Simplify each side (distribute and combine like terms)
3. $-11x - 3 = 2$
  Subtract 8x from both sides
4. $-11x = 5$
  Add 3 to both sides
3. Steps, part 2
1. $x = \frac{5}{-11} = -\frac{5}{11}$
  Divide both sides by -11
4. The answer
$x = -\frac{5}{11} \approx -0.45454545$
x = -5/11 ≈ -0.45454545
5. Check
- x = -0.45454545: left side = -1.6363636, right side = -1.6363636 ✓

Transcript

The problem. Here is the problem: negative 3(x plus 1) equals 8x plus 2. A linear equation in x: isolate x using inverse operations.

Steps, part 1. Start with the equation. Simplify each side (distribute and combine like terms). Subtract 8x from both sides. Add 3 to both sides.

Steps, part 2. Divide both sides by negative 11.

The answer. So the answer is x equals negative 5 over 11 approximately negative 0.45454545. Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

Check. x equals negative 0.45454545: left side equals negative 1.6363636, right side equals negative 1.6363636, which checks out.

About linear equations

Solve one-variable linear equations, including ones with brackets and fractions, and check the solution.

Solve -3(x + 1) = 8x + 2: Animated Step-by-Step Lesson