Solve the equation using a method other than factoring. Show all your work. x² - 7x + 3 = 0

1 answer:

5 0

Completing the square

7/2=3.5
3.5^2=12.25
add that to both sides
x²-7x+12.25+3=12.25
factor perfect square
(x-3.5)²+3=12.25
minus 3 both sides
(x-3.5)²=9.25
square root both sides
x-3.5=+/-√9.25
add 3.5 to both sides
x=3.5+/-√9.25

x=3.5+√9.25 or 3.5-√9.25

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