Step-by-step explanation: Let's graph the equation y = -3x using its slope and y-intercept. The problem here is that our equation doesn't match up quite so well with the formula y = mx + b
Our slope or <em>m</em> which is represented by the coefficient of the x-term is clearly -3. However, you might be asking what is our y-intercept or <em>b</em>. Well, y = -3x can be thought of as y = -3x + 0. So you can now see that our <em>b</em> or y-intercept equals 0.
To graph the line, we start with the y-intercept. So our first point is a 0 on the y-axis and we call that point A. When the slope is a integer, you can change it to a fraction by putting it over 1. So our slope of -3 can be thought of as -3/1.
From point A, we would go down 3 units and over 1 unit to plot point B. Now we can connect points A and B like I did in the picture and we have our line.
Given:
The figure of a triangle.
To find:
The missing length.
Solution:
Let x be the missing length.
Basic proportionality theorem(BPT): According to this theorem, if a line is parallel to the one side of a triangle then that the line intersects the other two sides of the triangle in the same ratio.
Using Basic proportionality theorem, we get
Adding x on both sides, we get
The missing length is 3 Therefore, the correct option is D.