Question

In the given diagram, the line AB cuts the y-axis at the point C(10, 2) and passes through the point D(-3,-4). Find the slope and equation of the line CD.
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Answer 1

Answer:

y = 2x + 2

Step-by-step explanation:

To find the slope (gradient), use the formula:  $m=\frac{y_2-y_1}{x_2-x_1}$

where $m$ is the slope and $(x_1, y_1)$ and $(x_2, y_2)$ are the points C and D:

$m=\frac{y_2-y_1}{x_2-x_1}$

$m=\frac{-4-2}{-3-0}=2$

By inspection, we can see that the y-intercept is 2.

So using the equation of a straight line $y=mx+c$  where $m$ is the slope and $c$ is the y-intercept, the equation of the line CD is:

$y=2x+2$