Question

A line passes through the points (-1,-5) and (4,5) . The point (a.1) is also on the line. what is the value of a?

Answer 1

Explanation:

Let's first find the slope of the line using the 2 given points. That is:

`m =(5-(-5))/(4-(-1))=(5+5)/(4+1)=(10)/(5)=2`

So the slope is 2. Let's write the equation of the line now, using one of the points. I'll use (4, 5) cuz I don't care much for negatives:

y - 5 = 2(x - 4) and

y - 5 = 2x - 8 and

y = 2x - 8 + 5 so

y = 2x - 3

Now that we know the equation of the line, we can sub in 1 for y to solve for a:

1 = 2x - 3 and

4 = 2x so

x (a) = 2

So a = 2 and the point is (2, 1)