sat suite question viewer
In the xy-plane, line passes through the point and is parallel to the line represented by the equation . If line also passes through the point , what is the value of ?
Explanation
Choice C is correct. A line in the xy-plane can be represented by an equation of the form , where is the slope and is the y-coordinate of the y-intercept of the line. It's given that line passes through the point . Therefore, the y-coordinate of the y-intercept of line is . It's also given that line is parallel to the line represented by the equation . Since parallel lines have the same slope, it follows that the slope of line is . Therefore, line can be represented by the equation , where and . Substituting for and for in yields the equation , or . If line passes through the point , then when , for the equation . Substituting for and for in this equation yields , or .
Choice A is incorrect. This is the y-coordinate of the y-intercept of the line represented by the equation .
Choice B is incorrect. This is the slope of the line represented by the equation .
Choice D is incorrect. The line represented by the equation , not line , passes through the point .