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3 votes
3 votes
7. If x² + 4 = 29, then x² - 4 = ?
A. 5
B. √21
C. 21
D. 25
E. 33

User Thangchung
by
2.7k points

1 Answer

14 votes
14 votes

Answer:

21

Explanation:

So if x²+4=29 we need to find the value of x

ie. x²=29-4

x²=25

x=√25=±5

Plugging this into the equation it becomes

5²+4=29

now x²-4=5²-4=21

User Joe Harris
by
3.1k points
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