When writing an equation in slope-intercept form, does be have to be a positive number or can it be negative? For example, y=-3x-5.
positive means that t increases as x increases. The line rises up to the right
negative means that y decreases as x increases. The line falls down to the right.
Visit wolframalpha.com and type in a few functions to see how the value of m affects the graph.
For example, if you enter "y=-3x-5" it will show you the graph and some other info.
Steve, that was an excellent explanation.
aww, shucks. >scuff scuff<
When writing an equation in slope-intercept form, the slope of the line, represented by the coefficient of x, can be positive or negative. The equation y = mx + b is in slope-intercept form, where m is the slope of the line and b is the y-intercept (the point where the line crosses the y-axis).
In your example, y = -3x - 5, the slope is -3. The negative sign indicates that the line has a downward slope.
The slope-intercept form allows you to easily understand the slope of the line by looking at the coefficient of x. If the slope (m) is positive, the line goes upward from left to right. If the slope is negative, as in this case, the line goes downward from left to right.
The value of b in the equation y = mx + b represents the y-coordinate of the point where the line crosses the y-axis. In this case, b = -5, indicating that the line crosses the y-axis at the point (0, -5).
Remember, when writing an equation in slope-intercept form, the slope can be positive or negative, while the y-intercept can be any real number.