Solve x^2-8x=3 by completing the square. which is the solution set of the equation?

Question: x² - 8x = 3

First we factorise the x²-8x like so: (remember, you halve the 8 to get 4)

x² - 8x = 3

(x - 4)² - 16 = 3     .

(x - 4)² = 19

x - 4 = √19

x = 4±√19

x = 4±√19

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Some explanations:

in:  (x - 4)² - 16 = 3

we have to subtract 16.

If we didn't,  then  (x - 4)² would expand to x² - 8x + 16

We don't want this since x² - 8x + 16 is not the same as x² - 8x, so we have to subtract 16 to make it the same:

x² - 8x = (x - 4)² - 16             but    x² - 8x (x - 4)²    

step-by-step explanation:

i have done this all on a piece of paper but idk how to put it on here cuz it needs to be drawn

walter needs to make at least 5 more cookies but no more than 40. 5 ≥ x ≥ 40;

step-by-step explanation:

walter has to make a minimum of 20 cookies. he already has 15 cookies made, so he must make 5 more to meet the minimum.

the maximum amount of cookies he can make is 55. he already has 15, so he has to make no more than 40 more cookies to meet the maximum.