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Linear equationsAlgebraMiddle schoolabout 1:03

Solve -1(x - 7) = 8x - 5: animated lesson

A narrated, step-by-step linear equations video lesson with captions. Final answer: x = 4/3 ≈ 1.3333333.

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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
$-1~\left( x-7\right) = 8~ x-5$
2. Steps, part 1
1. $-1~\left( x-7\right) = 8~ x-5$
  Start with the equation
2. $-x + 7 = 8x - 5$
  Simplify each side (distribute and combine like terms)
3. $-9x + 7 = -5$
  Subtract 8x from both sides
4. $-9x = -12$
  Subtract 7 from both sides
3. Steps, part 2
1. $x = \frac{-12}{-9} = \frac{4}{3}$
  Divide both sides by -9
4. The answer
$x = \frac{4}{3} \approx 1.3333333$
x = 4/3 ≈ 1.3333333
5. Check
- x = 1.3333333: left side = 5.6666667, right side = 5.6666667 ✓

Transcript

The problem. Here is the problem: negative 1(x minus 7) equals 8x minus 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 8x from both sides. Subtract 7 from both sides.

Steps, part 2. Divide both sides by negative 9.

The answer. So the answer is x equals 4 over 3 approximately 1.3333333. Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

Check. x equals 1.3333333: left side equals 5.6666667, right side equals 5.6666667, which checks out.

About linear equations

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

Solve -1(x - 7) = 8x - 5: Animated Step-by-Step Lesson