Math Problem Statement

explain how to draw y = −5|x+3|

Solution

To graph the equation y=5x+3y = -5|x+3|, follow these steps:

1. Understand the Basic Shape:

The function y=x+3y = |x+3| is an absolute value function, which creates a "V" shape. The absolute value means that the graph reflects any negative values back to positive ones, making the graph symmetric around its vertex.

2. Transform the Graph:

  • Horizontal Shift: The expression x+3|x + 3| shifts the basic x|x| graph 3 units to the left. This changes the vertex of the graph from (0,0)(0, 0) to (3,0)(-3, 0).
  • Vertical Stretch and Reflection: The coefficient of 5-5 outside the absolute value causes two transformations:
    • Vertical Stretch: The factor 55 makes the graph steeper by multiplying the y-values by 5.
    • Reflection: The negative sign flips the graph upside down, meaning the "V" shape points downwards instead of upwards.

3. Plot the Vertex:

The vertex is at (3,0)(-3, 0). Start by plotting this point.

4. Find Other Points:

To get a sense of how steep the graph is, choose a few points to the left and right of the vertex and calculate their y-values:

  • For x=4x = -4, y=54+3=51=5y = -5|-4+3| = -5|1| = -5 So, the point is (4,5)(-4, -5).

  • For x=2x = -2, y=52+3=51=5y = -5|-2+3| = -5|1| = -5 So, the point is (2,5)(-2, -5).

  • For x=6x = -6, y=56+3=53=15y = -5|-6+3| = -5|3| = -15 So, the point is (6,15)(-6, -15).

  • For x=0x = 0, y=50+3=53=15y = -5|0+3| = -5|3| = -15 So, the point is (0,15)(0, -15).

5. Draw the Graph:

  • Plot the points you calculated: (3,0)(-3, 0), (4,5)(-4, -5), (2,5)(-2, -5), (6,15)(-6, -15), and (0,15)(0, -15).
  • Connect the points with straight lines to form the inverted "V" shape.
  • Remember, the vertex is the highest point, and the graph extends downward on both sides.

6. Label the Axes:

  • Ensure your axes are labeled properly, especially the y-values which will have negative numbers since the graph points downward.

This completes the graph of y=5x+3y = -5|x+3|. Would you like further details on any of the transformations or specific points?

5 Related Questions:

  1. How would the graph change if the coefficient of xx inside the absolute value was modified?
  2. What happens to the graph of y=5x+3y = -5|x+3| if we remove the negative sign?
  3. How do vertical and horizontal stretches/compressions affect absolute value functions in general?
  4. How would you graph y=3x2y = 3|x - 2|? What are the main differences?
  5. How does changing the vertex impact the symmetry of the graph?

Tip:

When graphing absolute value functions, always start by identifying the vertex and how the coefficients transform the graph. This simplifies plotting points.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Absolute Value Functions
Transformations

Formulas

y = -5|x + 3|

Theorems

Transformation of Absolute Value Functions
Vertical Stretch
Reflection Across the x-axis

Suitable Grade Level

Grades 9-11