{"id":"act_quizme:math:q3:03","source_id":"act_quizme","source_item_id":"math-q3-03","external_id":"88aff840e1bfcaf3","program":"ACT","section":"math","category_code":null,"category":null,"subcategory_code":null,"subcategory":null,"form_id":null,"passage_id":null,"position":3,"scored":true,"layout_warning":null,"stem":"Which of the following expressions is equivalent to (x squared minus y squared) minus (6x squared +4xy minus y squared) ( x 2 - y 2 ) - ( 6 x 2 + 4 x y - y 2 ) ?","stimulus":"","stimulus_html":null,"stem_html":"<div class=\"math-question-wrap\"><div class=\"item-content\" id=\"p30\"> \t\t\t\t\t \t\t\t\t\t<p>Which of the following expressions is equivalent to <span style=\"white-space: nowrap;\"><span class=\"visually-hidden\">(x squared minus y squared) minus (6x squared +4xy minus y squared)</span><math class=\"srTransform\"><mo>(</mo><mrow><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow><mo>)</mo><mo>-</mo><mo>(</mo><mrow><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow><mo>)</mo></math>?</span></p>  \t\t\t\t</div> \t\t\t\t</div>\n<div><div class=\"math-answer-select-wrap\"></div></div>","rationale_html":"<p><strong>A.</strong> <strong>Correct. </strong>First, apply the distributive property: <span style=\"white-space: nowrap;\"><math><mfenced><mrow><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>-</mo><mfenced><mrow><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>=</mo><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup><mo>-</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup></math>.</span> Next, group like terms to get <span style=\"white-space: nowrap;\"><math><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup></math>.</span> Finally, combine like terms to get <span style=\"white-space: nowrap;\"><math><mo>-</mo><mn>5</mn><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>4</mn><mi>x</mi><mi>y</mi></math>.</span></p><p><strong>B.</strong> <strong>Incorrect. </strong>When applying the distributive property, be sure that the negative gets distributed to all terms of the trinomial: <span style=\"white-space: nowrap;\"><math><mfenced><mrow><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>-</mo><mfenced><mrow><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>=</mo><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup><mo>-</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup></math>.</span> You may not have multiplied the last 2 terms by <span style=\"white-space: nowrap;\"><math><mo>-</mo><mn>1</mn></math>.</span></p><p><strong>C.</strong> <strong>Incorrect.</strong> Be sure to apply the distributive property to distribute the negative through the trinomial: <span style=\"white-space: nowrap;\"><math><mfenced><mrow><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>-</mo><mfenced><mrow><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></mrow></mfenced><mo>=</mo><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup><mo>-</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup></math>.</span> You may have ignored the negative sign and thus calculated <span style=\"white-space: nowrap;\"><math><msup><mi>x</mi><mn>2</mn></msup><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup><mo>+</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><msup><mi>y</mi><mn>2</mn></msup></math></span> or <span style=\"white-space: nowrap;\"><math><mn>7</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>-</mo><mn>2</mn><msup><mi>y</mi><mn>2</mn></msup></math>.</span></p><p><strong>D.</strong> <strong>Incorrect.</strong> Be careful with the signs when applying the distributive property. You may have used a plus sign wherever there was a minus sign to get <span style=\"white-space: nowrap;\"><math><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup><mo>+</mo><mn>6</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>+</mo><msup><mi>y</mi><mn>2</mn></msup></math></span> or <span style=\"white-space: nowrap;\"><math><mn>7</mn><msup><mi>x</mi><mn>2</mn></msup><mo>+</mo><mn>4</mn><mi>x</mi><mi>y</mi><mo>+</mo><mn>2</mn><msup><mi>y</mi><mn>2</mn></msup></math>.</span></p>","correct_answer":["A"],"equiv_key":"578aa94972a1c7c55766f134","has_media":false,"has_mathml":true,"has_table":false,"section_label":"Mathematics","options":[{"label":"A","content_html":"<p><span>negative 5x squared minus 4xy</span>-5x2-4xy</p>","ord":0},{"label":"B","content_html":"<p><span>negative 5x squared +4xy minus 2y squared</span>-5x2+4xy-2y2</p>","ord":1},{"label":"C","content_html":"<p><span>7x squared +4xy minus 2y squared</span>7x2+4xy-2y2</p>","ord":2},{"label":"D","content_html":"<p><span>7x squared +4xy+2y squared</span>7x2+4xy+2y2</p>","ord":3}],"passage":null,"attribution":{"source_id":"act_quizme","source_name":"ACT QuizMe official practice questions","rights_holder":"ACT Education Corp.","canonical_url":"https://quizme.act.org/","retrieved_from":"https://quizme.act.org/","attribution":"Official ACT practice questions © ACT Education Corp., from the QuizMe practice quizzes at quizme.act.org.","disclaimer":"ACT® is a registered trademark of ACT Education Corp., which is not affiliated with, does not sponsor, and does not endorse this project.","license":"ACT Education Corp. copyright. 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