Slope intercept form practice math 8 b
1. Find the equation of the line in slope-intercept form that passes through the points (2, 5) and (4, 9).
Step 1: Calculate the slope using the formula:
m = (y2 - y1) / (x2 - x1)
m = (9 - 5) / (4 - 2)
m = 4 / 2
m = 2
Step 2: Use the slope-intercept form of a line (y = mx + b) and substitute the slope (m) and one of the given points (2, 5) to find the y-intercept (b):
5 = 2(2) + b
5 = 4 + b
b = 1
Step 3: Write the equation of the line in slope-intercept form:
y = 2x + 1
2. Find the equation of the line passing through the point (3, -2) with a slope of 4 in slope-intercept form.
Step 1: Use the point-slope form of a line (y - y1 = m(x - x1)) and substitute the point (3, -2) and the slope (m = 4):
y - (-2) = 4(x - 3)
y + 2 = 4x - 12
Step 2: Convert the equation to slope-intercept form by isolating y:
y = 4x - 12 - 2
y = 4x - 14
The equation of the line passing through the point (3, -2) with a slope of 4 in slope-intercept form is y = 4x - 14.