how to solve x+7 sq -4 =0 algebraically?
回答 (3)
2016-02-21 4:58 am
Let u = x + 7
(x + 7)² - 4 = 0
u² - 4 = 0
(u + 2)(u - 2) = 0
u + 2 = 0 or u - 2 = 0
u = -2 or u = 2
x + 7 = -2 or x + 7 = 2
x = -9 or x = -5
(x + 7)² - 4 = 0
u² - 4 = 0
(u + 2)(u - 2) = 0
u + 2 = 0 or u - 2 = 0
u = -2 or u = 2
x + 7 = -2 or x + 7 = 2
x = -9 or x = -5
2016-02-21 6:19 am
well if sq means the square root of -4 its going to be imaginary, so that means x+7+i+2=0 is the same thing. then solve for x.
2016-02-21 4:55 am
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收錄日期: 2021-04-18 14:28:58
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