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Linear equationsAlgebraMiddle schoolabout 1:04

Solve -2(x + 3) = -9x + 7: animated lesson

A narrated, step-by-step linear equations video lesson with captions. Final answer: x = 13/7 ≈ 1.8571429.

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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
$-2~\left( x+3\right) = -9~ x+7$
2. Steps, part 1
1. $-2~\left( x+3\right) = -9~ x+7$
  Start with the equation
2. $-2x - 6 = -9x + 7$
  Simplify each side (distribute and combine like terms)
3. $7x - 6 = 7$
  Add 9x to both sides
4. $7x = 13$
  Add 6 to both sides
3. Steps, part 2
1. $x = \frac{13}{7} = \frac{13}{7}$
  Divide both sides by 7
4. The answer
$x = \frac{13}{7} \approx 1.8571429$
x = 13/7 ≈ 1.8571429
5. Check
- x = 1.8571429: left side = -9.7142857, right side = -9.7142857 ✓

Transcript

The problem. Here is the problem: negative 2(x plus 3) equals negative 9x plus 7. 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). Add 9x to both sides. Add 6 to both sides.

Steps, part 2. Divide both sides by 7.

The answer. So the answer is x equals 13 over 7 approximately 1.8571429. Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

Check. x equals 1.8571429: left side equals negative 9.7142857, right side equals negative 9.7142857, which checks out.

About linear equations

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

Solve -2(x + 3) = -9x + 7: Animated Step-by-Step Lesson