G3 | Maths Made Easy

G3

Question: Find the gradient of the straight line graph shown to the right. 

Answer: Remember we just need to find two numbers to describe our line: the gradient (m) and the y-axis intercept (c).

It’s easier if we start with the gradient. m=\dfrac{\text{change in y}}{\text{change in x}}=\dfrac{y_2-y_1}{x_2-x_1}=\dfrac{7-(-2)}{4-(-2)}=\dfrac{9}{6}=\frac{3}{2}

So our equation so far is y=\frac{3}{2}x+c.

C is always the y-intercept which we can see from the graph is 4.

Giving the final answer to as y = \frac{3}{2}x+4