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Linear equationsAlgebraMiddle schoolabout 0:48

Solve -7x + 7 = 16: animated lesson

A narrated, step-by-step linear equations video lesson with captions. Final answer: x = -9/7 ≈ -1.2857143.

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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 (0.3 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Solving an equation
$-7~ x+7 = 16$
2. Step by step
1. $-7~ x+7 = 16$
  Start with the equation
2. $-7x = 9$
  Subtract 7 from both sides
3. $x = \frac{9}{-7} = -\frac{9}{7}$
  Divide both sides by -7
3. The answer
$x = -\frac{9}{7} \approx -1.2857143$
x = -9/7 ≈ -1.2857143
4. Check
- x = -1.2857143: left side = 16, right side = 16 ✓

Transcript

The problem. Here is the problem: negative 7x plus 7 equals 16. A linear equation in x: isolate x using inverse operations.

Step by step. Start with the equation. Subtract 7 from both sides. Divide both sides by negative 7.

The answer. So the answer is x equals negative 9 over 7 approximately negative 1.2857143. Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

Check. x equals negative 1.2857143: left side equals 16, right side equals 16, which checks out.

About linear equations

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

Solve -7x + 7 = 16: Linear equations Step-by-Step Lesson