2. Solve the equation, if possible. Write irrational numbers in simplest radical form. Describe the strategy you used to get your solution and tell why you chose that strategy.
x^2 - 8x + 1 = 0
x^2 - 8x + 1 = 0
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You need to first find two numbers that multiply to 1 and add to -8. This is not possible so you must use the quadratic formula.
let a = 1, b = -8, and c = 1. It would look like this:
(-(-8) ± √(-8)^2 - 4(1)(1))/2(1). This simplifies to (8 ± 8 - 4)/2.
Now divide it all by 2 and get your final answer of 4 ± 2. This can actually be simplified into two different answers: 6 and 2.
So your two solutions are x = 6 and x = 2
let a = 1, b = -8, and c = 1. It would look like this:
(-(-8) ± √(-8)^2 - 4(1)(1))/2(1). This simplifies to (8 ± 8 - 4)/2.
Now divide it all by 2 and get your final answer of 4 ± 2. This can actually be simplified into two different answers: 6 and 2.
So your two solutions are x = 6 and x = 2
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Use the abc-formula.
a=1 b=-8 c=1
D=b^2-4*a*c
D=64-4=60
x=(8-V60)/(2*1) or x=(8+V60)/(2*1)
x=approx. -0,127 or x= approx. 7,873
a=1 b=-8 c=1
D=b^2-4*a*c
D=64-4=60
x=(8-V60)/(2*1) or x=(8+V60)/(2*1)
x=approx. -0,127 or x= approx. 7,873