To find the equation of the line that passes through the points (2, 1) and (4, 5), we can use the slope-intercept form of the line, which is given by:
y = mx + b
where m is the slope and b is the y-intercept. First, we need to calculate the slope (m) of the line using the formula:
m = (y2 – y1) / (x2 – x1)
Here, let:
- (x1, y1) = (2, 1)
- (x2, y2) = (4, 5)
Substituting the points into the slope formula:
m = (5 – 1) / (4 – 2) = 4 / 2 = 2
Now that we have the slope, we can find the y-intercept (b). We will use one of the points; let’s use (2, 1):
1 = 2(2) + b
Now solve for b:
1 = 4 + b
b = 1 – 4 = -3
Now that we have both m and b, we can write the equation of the line:
y = 2x – 3
In conclusion, the equation of the line that passes through the points (2, 1) and (4, 5) is:
y = 2x – 3
This equation tells us that for every increase of 1 in x, y increases by 2, starting from a y-intercept of -3 on the y-axis.