Please check if I did this right. If not please correct so I’ll understand what I did wrong.
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Answer:
7 inches by 7 inches
Step-by-step explanation:
x^2 -10x+25
Factor
What 2 numbers multiply to 25 and add to -10
-5*-5 = 25
-5+-5 = 10
(x-5) (x-5)
The dimensions are (x-5) by (x-5)
Substitute x=12 into the equation
(12-5) by (12-5)
7 by 7
The length is 7 and the width is 7
x² - 10x + 25 can be factored to (x - 5)(x - 5). If 12 = x, substitute 12 for x.
(12 - 5)(12 - 5) which equals (7)(7) or 49. You could also plug in 12 for x in the original equation, so 12² - (10)(12) + 25 → 144 - 120 + 25 → 49. The length and width is 49in²