Teach Genie
Teach it back in your own words, spot gaps, and remember it better.
In y=mx+cy=mx+cy=mx+c, mmm is the gradient and ccc is the y-intercept. The line crosses the y-axis at (0,c)(0,c)(0,c), so you can often read one point straight from the equation.
A positive gradient rises from left to right, and a negative gradient falls from left to right. Parallel lines have the same gradient, while non-vertical perpendicular lines have gradients that multiply to −1-1−1.
Question 1
5 marksA A\,A is the point (0,1)(0, 1)(0,1)
B B\,B is the point (10,6)(10, 6)(10,6)
The equation of the straight line through A A\,A and B B\,B is y=12x+1\displaystyle y = \frac{1}{2}x + 1y=21x+1
Identify the gradient and y-intercept in the equation y=mx+cy=mx+cy=mx+c.
Revision notes for Edexcel GCSE Maths Perpendicular Lines and the equation of a tangent. Open the guide for explanations and worked examples. Written against the Edexcel GCSE Maths (1MA1) specification, so the content matches what's examinable rather than general Maths background.
1 of 5
A line has equation y=−4x+7y=-4x+7y=−4x+7. What is the gradient of a line perpendicular to it?
