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A system of linear equations is shown on the graph. The equation of one of the lines is y = 1/2x + 4

A system of linear equations is shown on the graph. The equation of one of the lines-example-1

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Answer:


y = 3x - 1

Explanation:

From the graph given, let's label the lines as line A and line B. As indicated in the attachment below.

The equation of a line is given as y = mx + b

Where, m is the slope, which is:


m = (y2 - y1)/(x2 - x1)

b is the y-intercept. It is the point at which the line crosses or intercepts the y-axis. At this point, x = 0.

Having known this, let's figure out which of the lines has the equation, y = ½x + 4

From the equation given, it means the line's m = ½, and it's y-intercept (b), where the line intercepts the y-axis = 4.

Taking a look at line A and B that we've labelled in the attachment below, line A intercepts the y-axis at 4. This means value of b for line A = 4.

If we calculate the slope (m) for line A using the points labelled in the attachment below, we would arrive at ½ as the slope (m) of line A.

Therefore, the equation y = ½x + 4 is for line A.

Let's find the equation for line B.

=>Find the slope (m) of line B using any 2 coordinate pairs of line B.

We're using the 2 coordinates points, (0, -1), (-1, -4) as indicated in the attachment below.


m = (y2 - y1)/(x2 - x1)


m = (-4 - (-1))/(-1 - 0)


m = (-4 + 1))/(-1)


m = (-3))/(-1)


m = 3

Line B intercepts the y-axis at -1. Therefore, the y-intercept (b) for line B = -1

The equation for line B would be:


y = 3x - 1

A system of linear equations is shown on the graph. The equation of one of the lines-example-1
User Chintan Khetiya
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