Solve for x: 2x + 7 = x + 21.

Unlock all questions

This demo includes only 20 questions. Upgrade to access hundreds of questions, flashcards, exam simulations, and disable ads.

Full question bankExam simulationsFlashcards
From $24.99Unlock all

Study for the 7th Grade Math Test. Prepare with quizzes, flashcards, and detailed explanations for each question. Stay ready for your exam!

Multiple Choice

Solve for x: 2x + 7 = x + 21.

Explanation:
Solving linear equations by isolating the variable is what this question tests. To get x by itself, subtract x from both sides: 2x + 7 = x + 21 becomes x + 7 = 21. Then subtract 7 from both sides to finish isolating x: x = 14. Quick check: substitute 14 back in to see both sides equal 35 (2·14 + 7 = 28 + 7 = 35, and 14 + 21 = 35). The value that satisfies the equation is 14.

Solving linear equations by isolating the variable is what this question tests. To get x by itself, subtract x from both sides: 2x + 7 = x + 21 becomes x + 7 = 21. Then subtract 7 from both sides to finish isolating x: x = 14. Quick check: substitute 14 back in to see both sides equal 35 (2·14 + 7 = 28 + 7 = 35, and 14 + 21 = 35). The value that satisfies the equation is 14.

More Multiple Choice Questions
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy