(x - 3)^2 = 25?
A. x = ±5
B. x = ±√5
C. x = ±3
D. x = 8 and x = -2
回答 (11)
✔ 最佳答案
(x - 3)² = 25
x² - 6x +9 = 25
x² - 6x -16 = 0
(x -8)(x + 2) = 0
x = (8, -2)
(x-3)(x-3)=x^2-6x+9
x^2-6x+9-25=0
x^2-6x-16
D. x = 8 and x = -2
(x - 3)^2 = 25
Find the square root of both sides
x - 3 = +/-5
x = +/-5 + 3
x = + 5 + 3 = 8
x = -5 + 3 = -2
x = 8 and -2
Answer Letter D
D I verified it twice on paper
x - 3 = ± 5
x = 8 , x = - 2
OPTION D
(x – 3)² = 25
(x – 3) = â25 = ± 5
x – 3 = 5 or x – 3 = – 5
x = 8 or x = – 2 ----------- option D
---------
(x-3)^2=25
x^2-6x+9=25
x^2-6x+9-25=0
x^2-6x-16=0
(x-8)(x+2)=0
x-8=0
x=8,
x+2=0
x=-2
therefore X=8 and x=-2.so its letter D.
(x - 3)^2 = 25
x - 3 = 屉25
x - 3 = ±5
x - 3 = 5
x = 5 + 3
x = 8
x - 3 = -5
x = -5 + 3
x = -2
â´ x = -2 , 8
(answer D)
收錄日期: 2021-05-01 10:51:35
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