# what is the x-intercept? the x-coordinate of a point where the graph crosses the x- axis. what is...

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What is the x-intercept?The x-coordinate of a point where the graph crosses the x-

axis.• What is the y-intercept?The y-coordinate of a point where a graph crosses

the y-axis.

The x-intercept is the value of x when y=o.

The y-intercept is the value of y when x=o.

Finding interceptsFind the x-intercept and the y-intercept of the graph of the

equation 2x + 3y = 6

SOLUTIONFind the x-intercept of 2x + 3y = 6 Let y = 0.2x + 3y = 6 Write original equation.2x + 3(0) = 6 Substitute 0 for y.2x = 6 Solve for x. x = 3 The x-intercept is 3. The line crosses the x-axis at the

point (3, 0).

To find the y-intercept of 2x + 3y = 6, let x = 0.2x + 3y = 6 Write original equation.2(0) + 3y = 6 Substitute 0 for x.3y = 6 Solve for y.y = 2 The y-intercept is 2. The line crosses the y-axis at the point

(0, 2).

Use the graph to find the x-intercept and the y-intercept of the line

The x-intercept is -3 or (-3,0)

The y-intercept is 3 or (0,3)

1. Decide whether 2 is the x-intercept or the y-intercept of the line y = 2x + 2.Explain your choice. y-intercept; when x = 0, y = 2(0) + 2 = 2

2. How many points are needed to determine a line?Two Points

3. Describe a line that has no x-intercept.A line with y = a for any number except 0. For example, y = 2

4. Describe a line that has no y-intercept.A line with x = a for any number except 0. For example, x = -1

Check for Understanding

1. y = x + 2 -2; 22. y - 2x = 3 -3/2; 33. 5y = 5x + 15 -3; 34. x - y = 11; -1

Find the x- and y-intercept of the of the equation