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Find a negative real number such that the square of the sum of a number and 5 is equal to 48

User Hakamadare
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1 Answer

5 votes
Let x = negative real number ⇒x<0

from the statement above, we can generate an equation:
(x + 5)² = 48

\sqrt{(x+5)^(2) }=
√(48)
⇒ eliminate the square by getting the square root on both sides


√(48) = \left \{ {{=4 √(3) } \atop {=-4 √(3) }} \right.
⇒ the perfect square of a real number has one positive real number and a negative real number

transposing 5 to other side, we will arrive at two (2) values for x:


x_(1) = -5 - 4√3 = -11.928

x_(2) = -5 + 4√3 = 1.928

Since we are only looking at the negative real number, our answer will be -11.928, also equal to -5 - 4√3.


User Yasushi Shoji
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