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X- and y- intercepts and Rate of Change. Pre Algebra . What is the x- intercept?. The x- intercept is the x-coordinate of a point where the graph crosses the x-axis. The point would have 0 for y. The point is on the x-axis. Example: 3x + 4y = 12
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X- and y- interceptsand Rate of Change Pre Algebra
What is the x- intercept? • The x- intercept is the x-coordinate of a point where the graph crosses the x-axis. • The point would have 0 for y. • The point is on the x-axis. • Example: 3x + 4y = 12 To find the x-intercept, you have to put 0 in for y. 3x + 4(0) = 12 3x + 0 = 12 3x = 12 3x/3 = 12/3 x = 4
What is the y-intercept? • The y- intercept is the y-coordinate of a point where the graph crosses the y-axis. • The point would have 0 for x. • The point is on the y-axis. • Example: 3x + 4y = 12 To find the x-intercept, you have to put 0 in for y. 3(0) + 4y= 12 0 + 4y = 12 4y = 12 4y/4= 12/4 y = 3
To graph using the x- and y- intercept. Step 1: Determine the x- intercept. Step 2: Determine the y-intercept. Step 3: Graph the points. Step 4: Connect the two points with a ruler. Step 5: Label the line with the original equation.
Rate of Change/Slope Positive Rate of change: Negative Rate of change: No Slope: Undefined:
Stand Up Raise your left hand.
Assignment Rate of Change and Intercepts sheet.