Table of Contents

- 1 Is a negative number a stretch or compression?
- 2 What is shrinking and stretching?
- 3 How do you know if it is a horizontal stretch or compression?
- 4 How do you know if compression is horizontal or vertical?
- 5 How does horizontal stretch work?
- 6 What is vertical compression?
- 7 When do you get a compression and a stretch?
- 8 How are horizontal stretches and compressions related in Algebra?
- 9 How to write a formula for a compression?

## Is a negative number a stretch or compression?

If 0 < a < 1 you have a vertical compression and if a > 1 then you have a vertical stretching. When a is negative, then this vertical compression or vertical stretching of the graph is followed by a reflection across the x-axis.

## What is shrinking and stretching?

As in translating, when we change the input, the function changes to compensate. Thus, dividing the input by a constant stretches the function in the x direction, and multiplying the input by a constant shrinks the function in the x direction.

**What causes a horizontal stretch?**

Key Points When by either f(x) or x is multiplied by a number, functions can “stretch” or “shrink” vertically or horizontally, respectively, when graphed.

### How do you know if it is a horizontal stretch or compression?

If the constant is between 0 and 1, we get a horizontal stretch; if the constant is greater than 1, we get a horizontal compression of the function.

### How do you know if compression is horizontal or vertical?

When we multiply a function by a positive constant, we get a function whose graph is stretched or compressed vertically in relation to the graph of the original function. If the constant is greater than 1, we get a vertical stretch; if the constant is between 0 and 1, we get a vertical compression.

**How do you describe a horizontal stretch?**

A horizontal stretch or shrink by a factor of 1/k means that the point (x, y) on the graph of f(x) is transformed to the point (x/k, y) on the graph of g(x).

## How does horizontal stretch work?

What are Horizontal Stretches and Shrinks? Horizontal stretches and shrinks, respectively, horizontally pull the base graph, or push it together, while leaving the y-intercept unchanged to anchor the graph. if 0 < k < 1.

## What is vertical compression?

A vertical compression is essentially a squeezing or pushing of the graph towards the x-axis whereas a vertical stretching is the stretching of the graph away from the x-axis. Click on the item Compress or stretch graph vertically which is just beneath the graph.

**How do you do vertical compression?**

### When do you get a compression and a stretch?

If the constant is greater than 1, we get a vertical stretch; if the constant is between 0 and 1, we get a vertical compression. The graph below shows a function multiplied by constant factors 2 and 0.5 and the resulting vertical stretch and compression.

A General Note: Horizontal Stretches and Compressions 1 If b > 1 b > 1, then the graph will be compressed by 1 b 1 b. 2 If 0 < b< 1 0 < b < 1, then the graph will be stretched by 1 b 1 b. 3 If b < 0 b < 0, then there will be combination of a horizontal stretch or compression with a horizontal reflection.

**When do you use compression and stretches in graph function?**

When we multiply a function by a positive constant, we get a function whose graph is stretched or compressed vertically in relation to the graph of the original function. If the constant is greater than 1, we get a vertical stretch; if the constant is between 0 and 1, we get a vertical compression.

## How to write a formula for a compression?

How To: Given a description of a function, sketch a horizontal compression or stretch. 1 Write a formula to represent the function. 2 Set g(x) = f (bx) g ( x) = f ( b x) where b> 1 b > 1 for a compression or 0 for a stretch. More