Question 8
MediumOriginal questionFind if .
Show the answer and explanation
CorrectNot quiteAnswer A
Correct answer: A
Explanation
Expand both brackets: .
Simplify: , so .
Hence .
Worth noting
The minus sign in front of turns BOTH terms negative: . Writing gives 8.
- Concept
- Sign handling when a negative number multiplies a bracket
- Typical timeTypical
- 70 s
- Your timeYours
- —
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Ten questions from Linear and Quadratic Equations, at your own pace.