Respuesta :

For this case we have a graph of a function[tex]y = f (x)[/tex] whose slope is given by:

[tex]m =\frac{ f (x1) -f (x2)}{ x2-x1}\\[/tex]

When [tex]m> 0[/tex] the graph is increasing

When [tex]m <0[/tex]the graph is decreasing

So:

  • Interval (-∞, -1) slope [tex]m> 0[/tex], so the graph grows
  • Interval [-1,2.5] the slope [tex]m <0[/tex], so the graph decreases
  • Interval (2.5, ∞) slope [tex]m> 0[/tex], so the graph grows

Answer:

(-∞, -1) [tex]f (x)> 0\\[/tex]

 [-1, 2.5] [tex]f (x) <0\\[/tex]

(2.5, ∞) [tex]f (x)> 0[/tex]


The intervals in which graph of the function is positive are [tex]\boxed{\left( { - \infty , - 1} \right)}{\text{ and }}\boxed{\left( {2.5,\infty } \right)}[/tex] and intervals in which graph of the function is negative is [tex]\boxed{\left[ { - 1,2.5} \right]}.[/tex]

Further explanation:

Explanation:

The linear equation with slope m and y-intercept c is given as follows.

[tex]\boxed{y = mx + c}[/tex]

The formula for slope of line with points [tex]\left( {{x_1},{y_1}} \right) {\text{and} \left( {{x_2},{y_2}} \right)[/tex] can be expressed as,

[tex]\boxed{m = \frac{{{y_2} - {y_1}}}{{{x_2} - {x_1}}}}[/tex]

If the slope is greater than zero then the graph is increasing.

[tex]m> 0[/tex]

If the slope is less than zero then the graph is decreasing.

[tex]m< 0[/tex]

From the graph it has been observed that the graph slope of the function is greater than zero in interval [tex]\left( { - \infty , - 1} \right)[/tex]. Hence, the function is increases.

From the graph it has been observed that the graph slope of the function is less than zero in interval [tex]\left[ { - 1,2.5} \right].[/tex] Hence, the function is decreasing.

From the graph it has been observed that the graph slope of the function is greater than zero in interval [tex]\left( {2.5,\infty } \right)[/tex]. Hence, the function is increases.

The intervals in which graph of the function is positive are [tex]\boxed{\left( { - \infty , - 1} \right)}{\text{ and }}\boxed{\left( {2.5,\infty } \right)}[/tex] and intervals in which graph of the function is negative is [tex]\boxed{\left[ { - 1,2.5} \right]}.[/tex]

Learn more:

  1. Learn more about inverse of the functionhttps://brainly.com/question/1632445.
  2. Learn more about equation of circle brainly.com/question/1506955.
  3. Learn more about range and domain of the function https://brainly.com/question/3412497

Answer details:

Grade: High School

Subject: Mathematics

Chapter: Linear equation

Keywords: Slope, intercept, y- intercept, x- intercept, points, function, relation, graph, increasing, decreasing, strictly increasing, strictly decreases, interval, graph grows, positive, negative.