How do you find the gradient of a straight line?

Change in y divided by change in x between two points, subtracting in the same order. Check the sign against the slope you can see.

What does c mean in y = mx + c?

The y-intercept: the y-coordinate where the line crosses the y-axis, which is the value of y when x is 0.

Do I need a table of values every time?

No. Intercept plus gradient is enough to draw the line. A table helps when you do not yet trust the gradient.

Straight line graphs GCSE Maths questions

Straight line graphs GCSE Maths questionsStraight line graphs GCSE Maths questions: gradient, intercept, and y = mx + c from two points or a sketch. Plot and read them. Marked algebra practice.Start free GCSE Maths test · Pricing