{"id":"cb_practice_pdf:t6-math-m2-q18","source_id":"cb_practice_pdf","source_item_id":"t6-math-m2-q18","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-6","module_number":2,"position":18,"stem":"= 7x+ Line k is defined by y 1/8. Line j is perpendicular to line k in the xy-plane. What is the slope of line j? −8","stimulus":"","stimulus_html":null,"stem_html":"<p>= 7x+ Line k is defined by y 1/8. Line j is perpendicular to line k in the xy-plane. What is the slope of line j? −8</p>","rationale_html":"<p>=7 + 1 Choice B is correct. It’s given that line k is defined by y x 8. For an equation = + in slope-intercept form y mx b, m represents the slope of the line defined by this equation in the xy-plane and b represents the y-coordinate of the y-intercept of this line. Therefore, the slope of line k is 7. It’s also given that line j is perpendicular to line k in the xy-plane. Therefore, the slope of line j is the 1 - opposite reciprocal of the slope of line k. The opposite reciprocal of 7 is 7. 1 - Therefore, the slope of line j is 7. Choice A is incorrect. This is the opposite reciprocal of the y-coordinate of the y-intercept, not the slope, of line k. Choice C is incorrect. This is the y-coordinate of the y-intercept of line k, not the slope of line j. Choice D is incorrect. This is the slope of a line that is parallel, not perpendicular, to line k. 48 SAT PRACTICE TEST #6 ANSWER EXPLANATIONS SAT ANSWER EXPLANATIONS n MATH: MODULE 2</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>−</p>","ord":0},{"label":"B","content_html":"<p>1/7</p>","ord":1},{"label":"C","content_html":"<p>1/8 7</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}}