What is the slope-intercept formula?

• A. A=πr^2
• B. y = mx + b
• C. C=2πr
• D. A=1/2 bh

Answer: (B)

The main idea is to describe a straight line in a way that you can read off how steep it is and where it crosses the vertical axis. The slope-intercept form is written as y = mx + b, where y is the dependent value, x is the independent value, m is the slope, and b is the y-intercept (the point where the line crosses the y-axis).

The slope m tells you how much y changes for each unit increase in x, so a larger m means a steeper line. The intercept b shows where the line hits the y-axis when x equals zero, which helps you sketch the line quickly.

For example, if the equation is y = 3x - 2, the line crosses the y-axis at (0, -2) and climbs 3 units up for every 1 unit to the right. This form directly shows both steepness and vertical position.

The other formulas shown are for areas or circumference of shapes (such as a circle or a triangle) and do not describe a line in the coordinate plane, so they aren’t slope-intercept form.