QUESTION FOR 50 POINTS Solve this equation using an algebraic method: (x + 4)(x  4) = 9 Choices are: x=5 x=4 and x=4 x=9 x=5 and x=5
Mathematics
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Question
QUESTION FOR 50 POINTS
Solve this equation using an algebraic method: (x + 4)(x  4) = 9
Choices are:
x=5
x=4 and x=4
x=9
x=5 and x=5
Solve this equation using an algebraic method: (x + 4)(x  4) = 9
Choices are:
x=5
x=4 and x=4
x=9
x=5 and x=5
2 Answer

1. User Answers irspow
(x+4)(x4)=9 expand left side by performing indicated multiplication...
x^216=9 add 16 to both sides
x^2=25 take the square root of both sides...
x=±5
x=5 and 5
So the answer would be the bottom choice. 
2. User Answers phillipino2002
the answer is
x=5 and x=5