{"id":"cb_question_bank:641f811a-1196-4754-9a79-1f08fb65c245","source_id":"cb_question_bank","source_item_id":"641f811a-1196-4754-9a79-1f08fb65c245","external_id":null,"ibn":"05103-DC","question_id":"12983c1e","program":"SAT","module":"math","domain_code":"H","domain":"Algebra","skill_code":"H.B.","skill":"Linear functions","difficulty":"E","score_band":2,"answer_type":"mcq","answer_source":"key","layout_warning":null,"form_id":null,"module_number":null,"position":null,"stem":"Some values of the linear function f are shown in the table above. Which of the following defines f ?","stimulus":"The figure presents a 2-column table with 3 rows of data. The heading for the first column is “x.” The heading for the second column is “f of x.” The three rows of data are as follows. Row 1. x, 1; f of x, 5. Row 2. x, 3; f of x, 13. Row 3. x, 5; f of x, 21.","stimulus_html":"<div class=\"stimulus_reference \">\n\t<div class=\"passage \">\n\t\t<div class=\"prose style:1 \">\n\t\t\t<div class=\"image-options-wrapper image-wrap-center 37663 tcp-752cafb3-08f5-490f-af66-947a5131ae0a\"><img src=\"/api/assets/a61385f1c8b2af4d45355ac9f3bcd4a3a11ec387e34bc63790769e4e4b202dc5\" alt=\"The figure presents a 2-column table with 3 rows of data. The heading for the first column is “x.” The heading for the second column is “f of x.” The three rows of data are as follows.\n\nRow 1. x, 1; f of x, 5.\nRow 2. x, 3; f of x, 13.\nRow 3. x, 5; f of x, 21.\n\" width=\"60\" height=\"67\"></div>\n\t\t</div>\n\t</div>\n</div>\n","stem_html":"<p class=\"stem_paragraph \">Some values of the linear function <span class=\"italic\">f</span> are shown in the table above. Which of the following defines <span class=\"italic\">f </span>?</p>\n","rationale_html":"<p>Choice C is correct. Because <span class=\"italic\">f</span> is a linear function of <span class=\"italic\">x</span>, the equation <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/85d346e80696592103a24156028b524124e60208306aaa1d2b81366c09e2f8e4\" alt=\"f of x equals, m x plus b\"></span>, where <span class=\"italic\">m</span> and <span class=\"italic\">b</span> are constants, can be used to define the relationship between <span class=\"italic\">x</span> and <span class=\"italic\">f</span> (<em>x</em>). In this equation, <span class=\"italic\">m</span> represents the increase in the value of <span class=\"italic\">f</span> (<span class=\"italic\">x</span>) for every increase in the value of <span class=\"italic\">x</span> by 1. From the table, it can be determined that the value of <span class=\"italic\">f</span> (<span class=\"italic\">x</span>) increases by 8 for every increase in the value of <span class=\"italic\">x</span> by 2. In other words, for the function <em>f</em> the value of <span class=\"italic\">m</span> is <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/1cf3ca6125063879a4d297324a1045a2d445d2dcd5284cceeb025bd61d46fb4a\" alt=\"eight halves\"></span>, or 4. The value of <span class=\"italic\">b</span> can be found by substituting the values of <span class=\"italic\">x</span> and <span class=\"italic\">f</span> (<span class=\"italic\">x</span>) from any row of the table and the value of <span class=\"italic\">m</span> into the equation <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/85d346e80696592103a24156028b524124e60208306aaa1d2b81366c09e2f8e4\" alt=\"f of x equals, m x plus b\"></span> and solving for <span class=\"italic\">b</span>. For example, using <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6e4319fe2c5755fc5aa3f69e1a43b989d061cbb17c450f24b51a6616f131de4b\" alt=\"x equals 1\"></span>, <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/a78eb9edb4471a8d95dbf6024484e12f66dd9f7efc7bce364de0d3b24e166641\" alt=\"f of x equals 5\"></span>, and <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/2bc845b9cf290820bd628ea4e64a4fbe344b447b35ee08fdbbe16d967bd0f24f\" alt=\"m equals 4\"></span> yields <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/fbe350486f043dbb3ad52973f54d2f9a00291299167d75cbdd86340e9367494a\" alt=\"5 equals, 4 times 1, plus b\"></span>. Solving for <span class=\"italic\">b</span> yields <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/e7591c90d04d93ac61bcfeb9f58ebd5ee6cdc220f79042ac9f5902b21b97363f\" alt=\"b equals 1\"></span>. Therefore, the equation defining the function <span class=\"italic\">f</span> can be written in the form <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6b1e80d16755a1a7dcd70b131994064a9006ddb8809b5d152011e917c87b7cb8\" alt=\"f of x equals, 4 x plus 1\"></span>.</p><p>Choices A, B, and D are incorrect. Any equation defining the linear function <span class=\"italic\">f</span> must give values of <span class=\"italic\">f</span> (<span class=\"italic\">x</span>) for corresponding values of <span class=\"italic\">x</span>, as shown in each row of the table. According to the table, if <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/ceba1165e53a8baa1cf03f75cde85da34750b8ab2728ef25385d77f80f8276c5\" alt=\"x equals 3\"></span>, <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/4f600dc21eafb900216c80af8ccc68c4b742de83c90299f27a0b218ed2e54c7b\" alt=\"f of x equals 13\"></span>. However, substituting <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/ceba1165e53a8baa1cf03f75cde85da34750b8ab2728ef25385d77f80f8276c5\" alt=\"x equals 3\"></span> into the equation given in choice A gives <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/1a305f5832494ccb8e038d29f06132fbd222d00a28f4bb935aab5ba7cb403b39\" alt=\"f of 3 equals, 2 times 3, plus 3\"></span>, or <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/f09e46d56d411d423ab13008729fc646d63ee909833ab8a2a474f5d0c88dfa8f\" alt=\"f of 3 equals 9\"></span>, not 13. Similarly, substituting <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/ceba1165e53a8baa1cf03f75cde85da34750b8ab2728ef25385d77f80f8276c5\" alt=\"x equals 3\"></span> into the equation given in choice B gives&nbsp;<span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/292e669fcdce9da49216d01d06b1497d0fa61bf9d07a062d3f755f7012722f8e\" alt=\"f of 3 equals, 3 times 3, plus 2\"></span>, or <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/3c02ac4864a7361a24f3a6016dc4c50083338f396dd77af130455f57362fc16b\" alt=\"f of 3 equals 11\"></span>, not 13.</p><p>Lastly, substituting <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/ceba1165e53a8baa1cf03f75cde85da34750b8ab2728ef25385d77f80f8276c5\" alt=\"x equals 3\"></span> into the equation given in choice D gives <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/4357987701b6a0dd8699e1f9d1c6d1a4f21a6d38037687ce34e3c6aac6bab865\" alt=\"f of 3 equals, 5 times 3\"></span>, or <span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/bc7a165218368f7e80d45fed473fce4d51f4fd67b748d2c7da02313950ec7c19\" alt=\"f of 3 equals 15\"></span>, not 13. Therefore, the equations in choices A, B, and D cannot define <span class=\"italic\">f</span>.</p><p>&nbsp;</p><p></p>\n","correct_answer":["C"],"has_media":true,"has_mathml":false,"has_table":false,"source_created_at":"2023-08-02T20:25:59.628000+00:00","source_updated_at":"2023-08-02T20:25:59.628000+00:00","options":[{"label":"A","content_html":"<p><span class=\"math_expression \"><span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/1af848982fcfd130ff5cd664294edcdaa9223e56fd75192b161d794a1db3c103\" alt=\"f of x equals, 2 x plus 3\"></span></span></p>\n","ord":0},{"label":"B","content_html":"<p><span class=\"math_expression \"><span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/2da6191c1c82312fa3034808320c10f325b157e31047aa8537363e5c609046e9\" alt=\"f of x equals, 3 x plus 2\"></span></span></p>\n","ord":1},{"label":"C","content_html":"<p><span class=\"math_expression \"><span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/6b1e80d16755a1a7dcd70b131994064a9006ddb8809b5d152011e917c87b7cb8\" alt=\"f of x equals, 4 x plus 1\"></span></span></p>\n","ord":2},{"label":"D","content_html":"<p><span class=\"math_expression \"><span class=\"math-container\"><img align=\"middle\" role=\"math\" class=\"math-img\" src=\"/api/assets/58218aee0524299be20726cabb4e9a7e34a4fb4f2a03ef4fb1d59801aaf1f42e\" alt=\"f of x equals, 5 x \"></span></span></p>\n","ord":3}],"attribution":{"source_id":"cb_question_bank","source_name":"College Board digital SAT question bank (community dump)","rights_holder":"College Board","canonical_url":"https://satsuitequestionbank.collegeboard.org/","retrieved_from":"https://raw.githubusercontent.com/mdn522/sat-question-bank/main/data/cb-digital-questions.json","attribution":"SAT practice questions © College Board, from the official SAT Suite Question Bank. Retrieved via the community dump at github.com/mdn522/sat-question-bank.","disclaimer":"SAT® and PSAT/NMSQT® are trademarks registered by the College Board, which is not affiliated with, does not sponsor, and does not endorse this project.","license":"College Board copyright; source repository carries no licence. Local use only.","redistributable":false,"item_count":2017}}