Question

Difficulty: EasyCoordinate Geometry and Lines

Line LL is defined by the equation 2x+y=62x + y = 6 in the xyxy-plane. Which of the following statements about line LL must be true? Select all that apply.

  1. The slope of line LL is 2-2.Answer
  2. The xx-intercept of line LL is (3,0)(3, 0).Answer
  3. C
    The slope of line LL is 12-\frac{1}{2}.
  4. D
    A line perpendicular to line LL has a slope of 2-2.
  5. E
    The yy-intercept of line LL is (0,6)(0, -6).

Answer

The slope of line LL is 2-2, and the xx-intercept of line LL is (3,0)(3, 0).
The given line equation 2x+y=62x + y = 6 can be rewritten in slope-intercept form y=2x+6y = -2x + 6. This directly shows that the slope is 2-2. Setting y=0y = 0 gives 2x=6    x=32x = 6 \implies x = 3, so the xx-intercept is (3,0)(3, 0). Therefore, both the statement that the slope is 2-2 and the statement that the xx-intercept is (3,0)(3, 0) are correct.

Step-by-Step Solution

1
Convert the equation to slope-intercept form (y=mx+by = mx + b).
y=2x+6y = -2x + 6
This isolates yy to clearly reveal the slope m=2m = -2 and the yy-intercept (0,6)(0, 6).
2
Find the xx-intercept by setting y=0y = 0.
2x+0=6    x=32x + 0 = 6 \implies x = 3, giving coordinate (3,0)(3, 0)
The xx-intercept is the point where the line crosses the xx-axis.
3
Determine perpendicular slope rules.
Perpendicular slope =12=12= -\frac{1}{-2} = \frac{1}{2}
Perpendicular lines have negative reciprocal slopes, not identical slopes.

Key Concept

Linear equations, slope-intercept form, intercepts, and perpendicular slopes in coordinate geometry.
Estimated Time:1m 0s
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