Question

A is the point (-2, 0) and B is the point (0, 4).Find the equation of the straight line joining A and B.

Answer 1

Answer:

y = 2*x + 4

Step-by-step explanation:

We know that a linear function can be written as:

y = a*x + b

Where a is the slope and b is the y-intercept.

We know that if this line passes through the points (x₁, y₁) and (x₂, y₂) the slope can be written as:

a = (y₂ - y₁)/(x₂ - x₁)

So, here we know that our line must pass through the points (-2,0) and (0, 4)

Then the slope of this line is:

a = (4 - 0)/(0 - (-2))

a = 4/2 = 2

Then our line is something like:

y = 2*x + b

Now, to find the value of b we can use one of these two points, for example if we use the point (-2, 0), we know that, when x = -2, we must have y = 0.

0 = 2*(-2) + b

0 = -4 + b

4 = b

Then the equation for our line is:

y = 2*x + 4