Answer:
x = {-1/5, 1}
Explanation:
(5x - 2)² - 1 = 8
Add 1 to both sides
(5x - 2)² = 9
Take the square root of both sides
5x - 2 = ±3
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Solution I for 5x - 2 = +3
5x - 2 = 3
add 2 to both sides
5x = 5
Divide both sides by 5
x = 1
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Solution II for 5x - 2 = -3
5x - 2 = -3
add 2 to both sides
5x = -1
Divide both sides by 5
x = -1/5
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x = {-1/5, 1}