What Is The $y$-intercept Of The Graph Of The Equation $y = X^2 - 5x + 4$?
Introduction
The $y$-intercept of a graph is the point at which the graph intersects the $y$-axis. In other words, it is the value of $y$ when $x = 0$. To find the $y$-intercept of the graph of the equation $y = x^2 - 5x + 4$, we need to substitute $x = 0$ into the equation and solve for $y$.
Understanding the Equation
The given equation is a quadratic equation in the form $y = ax^2 + bx + c$, where $a = 1$, $b = -5$, and $c = 4$. This type of equation represents a parabola, which is a U-shaped curve that opens upwards or downwards. The graph of the equation $y = x^2 - 5x + 4$ will be a parabola that opens upwards, since the coefficient of $x^2$ is positive.
Finding the $y$-Intercept
To find the $y$-intercept, we need to substitute $x = 0$ into the equation. This means that we need to replace every instance of $x$ with $0$ and simplify the resulting expression.
import sympy as sp

x = sp.symbols('x')
equation = x**2 - 5*x + 4
y_intercept = equation.subs(x, 0)
print(y_intercept)
When we run this code, we get the following output:
4
This means that the $y$-intercept of the graph of the equation $y = x^2 - 5x + 4$ is $y = 4$.
Graphing the Equation
To visualize the graph of the equation, we can use a graphing tool or software. Here is a graph of the equation $y = x^2 - 5x + 4$:
As we can see from the graph, the $y$-intercept is indeed at the point $(0, 4)$.
Conclusion
In this article, we have found the $y$-intercept of the graph of the equation $y = x^2 - 5x + 4$. We have used the concept of quadratic equations and the properties of parabolas to find the $y$-intercept. We have also graphed the equation to visualize the $y$-intercept. The $y$-intercept is an important concept in mathematics, and it has many applications in various fields such as physics, engineering, and economics.
Applications of the $y$-Intercept
The $y$-intercept has many applications in various fields. Here are a few examples:
- In physics, the $y$-intercept can be used to find the initial velocity of an object.
- In engineering, the $y$-intercept can be used to design and optimize systems such as bridges and buildings.
- In economics, the $y$-intercept can be used to model and analyze economic systems.
Final Thoughts
In conclusion, the $y$-intercept is an important concept in mathematics that has many applications in various fields. We have found the $y$-intercept of the graph of the equation $y = x^2 - 5x + 4$ using the concept of quadratic equations and the properties of parabolas. We have also graphed the equation to visualize the $y$-intercept. The $y$-intercept is a fundamental concept in mathematics that has many practical applications.
References
- [1] Khan Academy. (n.d.). Quadratic Equations. Retrieved from https://www.khanacademy.org/math/algebra/x2f-quadratic-equations
- [2] Wolfram MathWorld. (n.d.). Parabola. Retrieved from https://mathworld.wolfram.com/Parabola.html
- [3] MIT OpenCourseWare. (n.d.). 18.01 Single Variable Calculus. Retrieved from https://ocw.mit.edu/courses/mathematics/18-01-single-variable-calculus-fall-2007/
Further Reading
- [1] Algebra and Trigonometry by Michael Sullivan
- [2] Calculus by Michael Spivak
- [3] Linear Algebra and Its Applications by Gilbert Strang
Introduction
In our previous article, we discussed the concept of the $y$-intercept of a graph and how to find it using the equation $y = x^2 - 5x + 4$. In this article, we will answer some frequently asked questions about the $y$-intercept and provide additional information to help you understand this concept better.
Q&A
Q1: What is the $y$-intercept of a graph?
A1: The $y$-intercept of a graph is the point at which the graph intersects the $y$-axis. It is the value of $y$ when $x = 0$.
Q2: How do I find the $y$-intercept of a graph?
A2: To find the $y$-intercept of a graph, you need to substitute $x = 0$ into the equation of the graph and solve for $y$.
Q3: What is the difference between the $y$-intercept and the $x$-intercept?
A3: The $y$-intercept is the point at which the graph intersects the $y$-axis, while the $x$-intercept is the point at which the graph intersects the $x$-axis. In other words, the $y$-intercept is the value of $y$ when $x = 0$, while the $x$-intercept is the value of $x$ when $y = 0$.
Q4: Can the $y$-intercept be negative?
A4: Yes, the $y$-intercept can be negative. For example, if the equation of the graph is $y = -x^2 + 5x - 4$, the $y$-intercept would be $y = -4$.
Q5: How do I graph a function with a $y$-intercept?
A5: To graph a function with a $y$-intercept, you need to find the $y$-intercept by substituting $x = 0$ into the equation of the function. Then, you can use this point as a reference to draw the graph of the function.
Q6: Can the $y$-intercept be a complex number?
A6: Yes, the $y$-intercept can be a complex number. For example, if the equation of the graph is $y = x^2 + 5x + 4$, the $y$-intercept would be $y = 4 + 5i$, where $i$ is the imaginary unit.
Q7: How do I find the $y$-intercept of a graph with a quadratic equation?
A7: To find the $y$-intercept of a graph with a quadratic equation, you need to substitute $x = 0$ into the equation and solve for $y$. This will give you the $y$-intercept of the graph.
Q8: Can the $y$-intercept be a function of another variable?
A8: Yes, the $y$-intercept can be a function of another variable. For example, if the equation of the graph is $y = x^2 + 5x + 4 + 2t$, where $t$ is a parameter, the $y$-intercept would be a function of $t$.
Conclusion
In this article, we have answered some frequently asked questions about the $y$-intercept of a graph and provided additional information to help you understand this concept better. We hope that this article has been helpful in clarifying any doubts you may have had about the $y$-intercept.
Further Reading
- [1] Khan Academy. (n.d.). Quadratic Equations. Retrieved from https://www.khanacademy.org/math/algebra/x2f-quadratic-equations
- [2] Wolfram MathWorld. (n.d.). Parabola. Retrieved from https://mathworld.wolfram.com/Parabola.html
- [3] MIT OpenCourseWare. (n.d.). 18.01 Single Variable Calculus. Retrieved from https://ocw.mit.edu/courses/mathematics/18-01-single-variable-calculus-fall-2007/
References
- [1] Algebra and Trigonometry by Michael Sullivan
- [2] Calculus by Michael Spivak
- [3] Linear Algebra and Its Applications by Gilbert Strang