Find all real solutions to the equation |2x - 7| = 13.
Answer and explanation
Correct answer: C. x = -3 and x = 10
- Step 1: Set up the two cases: 2x - 7 = 13 or 2x - 7 = -13. Step 2. Case 1: 2x = 20 => x = 10. Step 3. Case 2: 2x = -6 => x = -3. Answer: x = -3 and x = 10. Why not the others: The other combinations represent sign inversion errors during step 2 or 3.
Practise more Algebra, Equations, Exponents and Sequences.
Free questions with an explanation for every one, and full timed Nationella prov (Sweden) mock tests.
More Algebra, Equations, Exponents and Sequences questions
- Solve the linear equation for x: 7x - 15 = 3x + 21.
- Solve the quadratic equation x^2 - 8x + 12 = 0 using the quadratic formula or factoring.
- Simplify the exponential expression (3x^3 y^2)^3.
- Evaluate the logarithmic expression log_2(64) + log_3(81).
- Find the 15th term of the arithmetic progression with first term a_1 = 4 and common difference d = 3.5.
- Factor the algebraic expression 9x^2 - 49y^2 completely.