sat-dog

Choice D is correct. The equation that defines line t in the xy-plane can be = + written in slope-intercept form y mx b, where m is the slope of line t and ( ) -1 =-1 0, b is its y-intercept. It’s given that line t has a slope of . Therefore, m . 3 3 -1 = + =- 1+ Substituting for m in the equation y mx b yields y x b, or 3 3 =- + x ( ) y b. It’s also given that line t passes through the point 9, 10 . 3 =- + x Substituting 9 for x and 10 for y in the equation y b yields 3 =-9+ =- + 10 b, or 10 3 b. Adding 3 to both sides of this equation yields 3 = =- + x =-x + 13 b. Substituting 13 for b in the equation y b yields y 13. 3 3 Choice A is incorrect and may result from conceptual or calculation errors. -1 Choice B is incorrect. This equation defines a line that has a slope of 9, not , ( ) ( ) 3 and passes through the point 0, 10, not 9, 10 . Choice C is incorrect. This ( ) ( ) equation defines a line that passes through the point 0, 10, not 9, 10 .