{"id":"cb_practice_pdf:t7-math-m1-q24","source_id":"cb_practice_pdf","source_item_id":"t7-math-m1-q24","external_id":null,"ibn":null,"question_id":null,"program":"SAT","module":"math","domain_code":null,"domain":null,"skill_code":null,"skill":null,"difficulty":null,"score_band":null,"answer_type":"mcq","answer_source":"rationale","layout_warning":"Part of this question was typeset outside the text flow — a fraction, subscript or similar — and PDF extraction re-inserted it in the wrong place. The wording is reliable; the symbols may be out of order.","form_id":"cb_practice_pdf:test-7","module_number":1,"position":24,"stem":"x y −2s 24 −s 21 s 15 The table shows three values of x and their corresponding values of y, where s is a constant. There is a linear relationship between x and y. Which of the following equations represents this relationship? +3 = 18","stimulus":"","stimulus_html":null,"stem_html":"<p>x y −2s 24 −s 21 s 15 The table shows three values of x and their corresponding values of y, where s is a constant. There is a linear relationship between x and y. Which of the following equations represents this relationship? +3 = 18</p>","rationale_html":"<p>Choice B is correct. The linear relationship between x and y can be represented - = - by an equation of the form y y1 m^x x1h, where m is the slope of the graph of , 1 1 the equation in the xy-plane and ^x yh is a point on the graph. The = s y lo 2- pe y 1 of a line can be found using two points on the line and the slope formula m x2- x 1. Each value of x and its corresponding value of y in the table can be represented by a - ,21 ,15 1 , 1 2 , 2 point ^x,yh. Substituting the points ^ s h and ^s h for ^x yh and ^x yh, = 15-21 =-6 respectively, in the slope formula yields m -- , which gives m 2 , or =-3 -3 s ^,1 sh5 1 , 1 s m . Substituting for m and the point ^s h for ^x yh in the equation - = s - s -15=- 3 - -3 y y1 m^x x1h yields y ^x sh. Distributing on the right-hand -15= s - 3 x+3 15 s side of this equation yields y . Adding to each side of this =- 3 x+18 s equation yields y . Multiplying each side of this equation by s yields s =-3 +18 3 + =18 sy x s. Adding 3x to each side of this equation yields x sy s. 3 + =18 Therefore, the equation x sy s represents this relationship. Choice A is incorrect and may result from conceptual or calculation errors. Choice C is incorrect and may result from conceptual or calculation errors. Choice D is incorrect and may result from conceptual or calculation errors. 37 SAT PRACTICE TEST #7 ANSWER EXPLANATIONS SAT ANSWER EXPLANATIONS n MATH: MODULE 1</p>","correct_answer":["B"],"has_media":false,"has_mathml":false,"has_table":false,"source_created_at":null,"source_updated_at":null,"options":[{"label":"A","content_html":"<p>sx y s 3x+sy = 18s</p>","ord":0},{"label":"B","content_html":"<p>3x+sy = 18</p>","ord":1},{"label":"C","content_html":"<p>sx+3y = 18</p>","ord":2},{"label":"D","content_html":"","ord":3}],"attribution":{"source_id":"cb_practice_pdf","source_name":"College Board full-length SAT practice tests (PDF)","rights_holder":"College Board","canonical_url":"https://satsuite.collegeboard.org/practice/practice-tests/paper","retrieved_from":"https://satsuite.collegeboard.org/practice/practice-tests/paper","attribution":"Full-length SAT practice tests 4–11 © College Board, published free at satsuite.collegeboard.org.","disclaimer":"Extracted from PDF layout: equations, figures and tables do not survive intact. Use the original PDFs for anything the text renders poorly. SAT® is a trademark registered by the College Board, which is not affiliated with and does not endorse this project.","license":"College Board copyright. Free to download; not licensed for redistribution.","redistributable":false,"item_count":905}}