Find the product of all possible real values of x satisfying|x + 5|x -...
∣x+5∣x−7∣∣ + ∣6x+7∣x−7∣∣ = 79
Case 1: x > = 7,
∣x+5∣x−7∣∣ + ∣6x+7∣x−7∣∣ = 79
∣x + 5x − 35∣ + ∣6x+7x−49∣ = 79
∣6x−35∣ + ∣13x−49∣ = 79
6x − 35 + 13x − 49 = 79
19x = 163
x = 163/19
Case 2: x < 7,
∣x+5 ∣x−7∣∣ + ∣6x+7∣ x−7∣∣ = 79
∣x−5x + 35 ∣ + ∣6x − 7x + 49∣ = 79
∣35−4x∣ + ∣49−x∣ = 79
35 − 4x + 49 − x = 79
5 × x = 5
x = 1
Product = 163/19
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Find the product of all possible real values of x satisfying|x + 5|x -...
Solution:
We can observe that x = 7 is not a valid solution since it makes the expression undefined.
| x 5 |x - 7| | 6x 7 | x - 7 | = 79
Let's consider each absolute value separately and we will combine them later.
Case 1: x < />
|x 5| = -(x - 5)
So, the expression becomes:
-(x - 5) * |x - 7| * |6x + 7| * |x - 7| = 79
Case 1.1: x < 5="" and="" 6x="" +="" 7="" />< />
|6x + 7| = -(6x + 7)
-(x - 5) * |x - 7| * -(6x + 7) * |x - 7| = 79
Simplifying further:
(6x + 7) * (x - 5) * (x - 7)^2 = -79
Case 1.2: x < 5="" and="" 6x="" +="" 7="" /> 0
|6x + 7| = 6x + 7
-(x - 5) * |x - 7| * (6x + 7) * |x - 7| = 79
Simplifying further:
(6x + 7) * (x - 5) * (x - 7)^2 = 79
Case 2: x > 5
|x 5| = (x - 5)
So, the expression becomes:
(x - 5) * |x - 7| * |6x + 7| * |x - 7| = 79
Case 2.1: x > 5 and 6x + 7 < />
|6x + 7| = -(6x + 7)
(x - 5) * |x - 7| * -(6x + 7) * |x - 7| = 79
Simplifying further:
(6x + 7) * (x - 5) * (x - 7)^2 = -79
Case 2.2: x > 5 and 6x + 7 > 0
|6x + 7| = 6x + 7
(x - 5) * |x - 7| * (6x + 7) * |x - 7| = 79
Simplifying further:
(6x + 7) * (x - 5) * (x - 7)^2 = 79
Now, we can combine the results from all the cases:
(6x + 7) * (x - 5) * (x - 7)^2 = ±79
Simplifying further:
(6x + 7) * (x - 5) * (x - 7)^2 = 79 or (6x + 7) * (x - 5) * (x - 7)^2 = -79
Solving for x, we get:
x = -7/6, 5, 13/3, 7 + 2√