What is the greater solution of ?
Answer and explanation
Correct answer: A. 7
- -2 is the smaller of the two solutions ().
- -7 reverses the signs of the roots, using factors .
- 5 is the sum of the roots () rather than a solution.
- -7 reverses the signs of the roots, using factors .
- 5 is the sum of the roots () rather than a solution.
- Step 1: Factor the quadratic equation: find two numbers that multiply to and add to , giving .
- Step 2: Set each factor to zero to find the roots: and .
- Step 3: Compare the two solutions: between and , the greater solution is .
Answer
7.
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