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

Answer:

Step-by-step explanation:

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

$m =\frac{5-(-5)}{4-(-1)}=\frac{5+5}{4+1}=\frac{10}{5}=2$

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)