Examples with solutions for Slope: Determine the slope of a linear function

Exercise #1

Given the linear function:

y=14x y=1-4x

What is the rate of change of the function?

Video Solution

Step-by-Step Solution

The given linear function is y=14x y = 1 - 4x . This can be rearranged to fit the standard format of a linear equation, y=mx+b y = mx + b , as y=4x+1 y = -4x + 1 .

In this form, the slope m m is simply the coefficient of x x . Here, m=4 m = -4 .

The slope of the linear function represents the rate of change of the function with respect to x x , meaning for every unit increase in x x , the value of y y decreases by 4 units.

Therefore, the rate of change of the function is m=4 m = -4 , which is option 4 among the given choices.

Thus, the solution to the problem is m=4 m = -4 .

Answer

m=4 m=-4

Exercise #2

Which best describes the function below?

y=23x y=2-3x

Video Solution

Step-by-Step Solution

To determine the characteristic of the function y=23x y = 2 - 3x , we will evaluate the slope:

  • The given function is in the form y=mx+b y = mx + b , which indicates a linear equation. Here, y=23x y = 2 - 3x can be rearranged as y=3x+2 y = -3x + 2 , showing that m=3 m = -3 .
  • The slope m m is 3-3.
  • In a linear function, the sign of the slope m m determines the function's behavior:
    • If the slope m m is positive (m>0 m > 0 ), the function is increasing.
    • If the slope m m is negative (m<0 m < 0 ), the function is decreasing.
    • If the slope m=0 m = 0 , the function is constant.
  • Since m=3 m = -3 , which is negative, we conclude that the function is decreasing.

Therefore, the function described by y=23x y = 2 - 3x is decreasing.

Answer

The function is decreasing.

Exercise #3

Given the linear function:

y=x4 y=x-4

What is the rate of change of the function?

Video Solution

Step-by-Step Solution

The problem asks to find the rate of change of the linear function y=x4 y = x - 4 . This function is in the form of y=mx+b y = mx + b , where:

  • m m is the slope, representing the rate of change of the function.
  • b b is the y-intercept, but it is not relevant for finding the rate of change.

For the function y=x4 y = x - 4 , we can compare it with the standard form y=mx+b y = mx + b to identify:

m=1 m = 1 .

Therefore, the rate of change of the function is determined by the coefficient of x x , which is 1.

Hence, the rate of change of the function is m=1 m = 1 .

The correct answer is: m=1 m = 1 .

Answer

m=1 m=1

Exercise #4

Choose the correct answer for the function.

y=x+1 y=-x+1

Video Solution

Step-by-Step Solution

Let's start with option A

In a linear function, to check if the functions are parallel, you must verify if their slope is the same.

y = ax+b

The slope is a

In the original formula:

 y = -x+1

The slope is 1

In option A there is no a at all, which means it equals 1, which means the slope is not the same and the option is incorrect.

 

Option B:

To check if the function passes through the points, we will try to place them in the function:

-1 = -(-2)+1

-1 = 2+1

-1 = 3

The points do not match, and therefore the function does not pass through this point.

 

Option C:

We rearrange the function, in a way that is more convenient:

y = -1-x

y = -x-1

You can see that the slope in the function is the same as we found for the original function (-1), so this is the solution!

 

Option D:

When the slope is negative, the function is decreasing, as the slope is -1, the function is negative and this answer is incorrect.

Answer

The graph is parallel to the graph of function

y=1x y=-1-x