Identify all of the following solutions of square root of x plus 14 end root plus 2 equals x.
x = -6, x = -1, x = -6 and x = -1, None of the above
Solution:
Given: Square root of x plus 14 end root plus 2 equals x
It can be mathematically written as
√(x + 14) + 2 = x
√(x + 14) = x - 2
By squaring on both sides
(x + 14) = (x - 2)2
Using the algebraic identity
(a - b)2 = a2 + b2 - 2ab
(x + 14) = x2 + 4 - 4x
x2 - 5x - 10 = 0
The formula for the standard form of quadratic equation ax2 + bx + c = 0 is written as
x = [-b ± √(b2 - 4ac)] / 2a
From the given equation we know that,
a = 1, b = -5, c = -10
Substituting it in the formula,
x = [ -(-5) ± √{(-5)2 - 4(1)(-10)} ] / 2(1)
x = [ 5 ± √{25 + 40} ] / 2
By further calculation,
x = [5 ± √65] / 2
Therefore, the values of x are (5 + √65)/2 and (5 - √65)/2.
Identify all of the following solutions of square root of x plus 14 end root plus 2 equals x.
Summary:
The solutions of square root of x plus 14 end root plus 2 equals x are (5 + √65)/2 and (5 - √65)/2.
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