Engineering Board Exam Reviewer · Quadratic Equations · medium
Solve x4-13x2+36=0.
- x=4, 9
- x= 2, 3
- x= 2, 6
- x= 3, 4
Answer
B. x= 2, 3
Solution
Let u=x2: u2-13u+36=0 (u-4)(u-9)=0 u=4,9. Then x= 2 and x= 3.
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