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How do you solve #-7n^2=-448#?

Answer 1

Savannah Anderson

#n=+-8#

Divide both sides by -7 so as to isolate the #n^2# term.

#(cancel(-7)^1 n^2)/cancel(-7)^1=(cancel(-448)^(64))/cancel(-7)^1rArrn^2=64#

now take the square root of both sides

#sqrt(n^2)=+-sqrt64rArrn=+-8#

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Answer 2

Kennedy Adams

#n= 8 or n = -8#

This is a quadratic equation, it can be solved by factorising.

#-7n^2 = -448 larr div" "-7 # to simplify. Divide on both sides.

#n^2 = 64 larr # make it =0

#n^2 -64 larr # difference of two squares.

#(n+8)(n-8) = 0#

Either factor can be equal to 0.

If #n+8 = 0 rarr n = -8#

If #n-8 = 0 rarr n = 8 #

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Answer 3

Eli Assouline

To solve the equation -7n^2 = -448, divide both sides by -7, then solve for n. The equation becomes n^2 = 64. Next, take the square root of both sides, remembering to consider both the positive and negative square roots. Therefore, n = ±8.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.