Question Video: Finding the 𝑦-Intercept Using a Graph of a Quadratic Function Mathematics

Identify the 𝑦-intercepts of the quadratic function 𝑓(π‘₯) = π‘₯Β² βˆ’ 1.

01:02

Video Transcript

Identify the 𝑦-intercepts of the quadratic function 𝑓 of π‘₯ equals π‘₯ squared minus one.

The quadratic 𝑓 of π‘₯ equals π‘₯ squared minus one is in the form 𝑓 of π‘₯ equals π‘Žπ‘₯ squared plus 𝑏π‘₯ plus 𝑐. In this form, the 𝑦-intercept is located at the point zero, 𝑐. The coefficient of π‘₯ squared, π‘Ž, equals one. The coefficient of the 𝑏-term would be equal to zero; we don’t have an π‘₯-term. And our 𝑐-value is equal to negative one. Using this method, we find a 𝑦-intercept at zero, negative one. Additionally, of course, we know that the 𝑦-intercept is the place that the graph crosses the 𝑦-axis. And if we look closely at this graph, that is halfway between zero and negative two, where 𝑦 equals negative one.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.