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Linear equationsAlgebraMiddle schoolabout 1:11

Solve -4(x - 1) = 7x + 5: animated lesson

A narrated, step-by-step linear equations video lesson with captions. Final answer: x = -1/11 ≈ -0.090909091.

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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
$-4~\left( x-1\right) = 7~ x+5$
2. Steps, part 1
1. $-4~\left( x-1\right) = 7~ x+5$
  Start with the equation
2. $-4x + 4 = 7x + 5$
  Simplify each side (distribute and combine like terms)
3. $-11x + 4 = 5$
  Subtract 7x from both sides
4. $-11x = 1$
  Subtract 4 from both sides
3. Steps, part 2
1. $x = \frac{1}{-11} = -\frac{1}{11}$
  Divide both sides by -11
4. The answer
$x = -\frac{1}{11} \approx -0.090909091$
x = -1/11 ≈ -0.090909091
5. Check
- x = -0.090909091: left side = 4.3636364, right side = 4.3636364 ✓

Transcript

The problem. Here is the problem: negative 4(x minus 1) equals 7x plus 5. 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 7x from both sides. Subtract 4 from both sides.

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

The answer. So the answer is x equals negative 1 over 11 approximately negative 0.090909091. Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

Check. x equals negative 0.090909091: left side equals 4.3636364, right side equals 4.3636364, which checks out.

About linear equations

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

Solve -4(x - 1) = 7x + 5: Animated Step-by-Step Lesson