Working with straight-line equations is fundamental in mathematics, especially as you move into advanced studies like A Level Maths. Knowing how to extract the gradient (slope) and y-intercept from different forms of linear equations is a crucial skill, and it frequently features in exam questions. In this blog post, we’ll work through how to find the gradient and y-intercept for the equation 4x - 5y + 1 = 0.
Step 1: Rearrange into the Slope-Intercept Form
The most useful form for identifying the gradient and y-intercept is the “slope-intercept” form:
y = mx + cLet’s start by rearranging the given equation: 4x - 5y + 1 = 0.
-5y = -4x - 1 y = \frac{-4x - 1}{-5} y = \frac{4}{5}x + \frac{1}{5}Step 2: Identify the Gradient and Y-Intercept:
The gradient (m) is \frac{4}{5}
The y-intercept (c) is \frac{1}{5}
Step 3: State the Final Answer
- Gradient: \frac{4}{5}
- Y-intercept: \frac{1}{5}
Why This Matters
Recognising and working with the slope and y-intercept is essential not just for exams, but for understanding graphs and solving real-world problems involving straight lines. Mastering these techniques will help you progress confidently through topics found in any A Level Maths Revision Course and beyond.