Question

98 POINTS Triangle ABC and triangle DEG are similar right triangles. Which proportion can be used to show that the slope of AC is equal to the slope of DG?

Answer 1

the answer is D)

0 − 4

−4 − (−7)

=

−4 − 8

−1 − (−10)

Answer 2

There are three steps in calculating the slope of a straight line when you are not given its equation.

Step One: Identify two points on the line.

Step Two: Select one to be (x1, y1) and the other to be (x2, y2).

Step Three: Use the slope equation to calculate slope.

Take a moment to work through an example where we are given two points.

Example

Let's say that points (15, 8) and (10, 7) are on a straight line. What is the slope of this line?

Step One: Identify two points on the line.

In this example we are given two points, (15, 8) and (10, 7), on a straight line.

Step Two: Select one to be (x1, y1) and the other to be (x2, y2).

It doesn't matter which we choose, so let's take (15, 8) to be (x2, y2). Let's take the point (10, 7) to be the point (x1, y1).

Step Three: Use the equation to calculate slope.

Once we've completed step 2, we are ready to calculate the slope using the equation for a slope: