2.3 and 2.4 Lines
- 1. 2.3 LINEAR FUNCTIONS AND SLOPE-INTERCEPT FORM 2.4 MORE ABOUT LINEAR EQUATIONS
- 2. LINEAR FUNCTIONS A linear function is a function whose graph is a line. We represent a linear function with a linear equation .
- 3. INTERCEPTS An intercept of a line is a point where a line crosses an axis. The y-intercept is the point at which the line crosses the y-axis. The x-intercept is the point at which the line crosses the x-axis.
- 4. TO FIND THE INTERCEPTS Set x = 0 and solve for y Set y = 0 and solve for x List your solutions as ordered pairs
- 5. EXAMPLE: WHAT ARE THE INTERCEPTS OF THE EQUATION?
- 6. SLOPE – INTERCEPT FORM The slope-intercept of an equation of a line is y = mx + b , where m is the slope of the line and (0, b ) is the y -intercept.
- 7. EXAMPLE: WHAT IS AN EQUATION OF THE LINE and the y-intercept is
- 8. EXAMPLE: WHAT IS AN EQUATION OF THE LINE
- 9. WORKING WITH LINEAR EQUATIONS We can rewrite a linear equation in slope – intercept form by solving for y.
- 10. EXAMPLE: WRITE THE EQUATION IN SLOPE – INTERCEPT FORM. WHAT ARE THE SLOPE AND Y-INTERCEPT.
- 11. EXAMPLE: WRITE THE EQUATION IN SLOPE – INTERCEPT FORM. WHAT ARE THE SLOPE AND Y-INTERCEPT.
- 12. POINT – SLOPE FORM Given a point and the slope of a line we can write the equation of the line in point – slope form
- 13. EXAMPLE: WRITING AN EQUATION GIVEN A POINT AND THE SLOPE A line passes through with slope What is an equation of the line?
- 14. EXAMPLE: WRITING AN EQUATION GIVEN A POINT AND THE SLOPE A line passes through with slope What is an equation of the line?
- 15. WRITING AN EQUATION GIVEN TWO POINTS Find the slope Substitute the slope and either point into the point-slope form
- 16. EXAMPLE A line passes through (3, 2) and (5, 8). What is an equation of the line in point-slope form?
- 17. STANDARD FORM Another form of the equation of a line is standard form . The coefficients of x and y and the constant should be intgers A should be postive!
- 18. WRITING AN EQUATION IN STANDARD FORM WITH INTEGER COEFFICIENTS Isolate the constant Eliminate Fractions: Multiply each side of the equation by the least common denominator of all fraction coefficients
- 19. EXAMPLE: WRITE THE EQUATION IN STANDARD FORM.