Use intercepts to graph an equation

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Presentation transcript:

Use intercepts to graph an equation EXAMPLE 2 Use intercepts to graph an equation Graph the equation x + 2y = 4. SOLUTION STEP 1 Find the intercepts. x + 2y = 4 x + 2y = 4 x + 2(0) = 4 0 + 2y = 4 x =  x-intercept 4 y =  y-intercept 2

EXAMPLE 2 Use intercepts to graph an equation STEP 2 Plot points. The x-intercept is 4, so plot the point (4, 0). The y-intercept is 2, so plot the point (0, 2). Draw a line through the points.

EXAMPLE 3 Use a graph to find intercepts The graph crosses the x-axis at (2, 0). The x-intercept is 2. The graph crosses the y-axis at (0, –1). The y-intercept is –1.

EXAMPLE 2 GUIDED PRACTICE Use intercepts to graph an equation for Examples 2 and 3 Graph the equation 6x + 7y = 42. Label the points where the line crosses the axes. 4. ANSWER

GUIDED PRACTICE for Examples 2 and 3 Identify the x-intercept and the y-intercept of the graph shown at the right. 5. –4, 2 ANSWER