What is the solution of the equation (x β 5)2 + 3(x β 5) + 9 = 0? Use u substitution and the quadratic formula to solve.
Question
Answer:
Answer:x = 1/5 (25 + 3 i sqrt(5)) or x = (-3 i sqrt(5) + 25)/5Step-by-step explanation using the quadratic formula:Solve for x:
5 (x - 5)^2 + 9 = 0
Expand out terms of the left hand side:
5 x^2 - 50 x + 134 = 0
x = (50 Β± sqrt((-50)^2 - 4Γ5Γ134))/(2Γ5) = (50 Β± sqrt(2500 - 2680))/10 = (50 Β± sqrt(-180))/10:
x = (50 + sqrt(-180))/10 or x = (50 - sqrt(-180))/10
sqrt(-180) = sqrt(-1) sqrt(180) = i sqrt(180):
x = (50 + i sqrt(180))/10 or x = (50 - i sqrt(180))/10
sqrt(180) = sqrt(4Γ9Γ5) = sqrt(2^2Γ3^2Γ5) = 2Γ3sqrt(5) = 6 sqrt(5):
x = (iΓ6 sqrt(5) + 50)/10 or x = (-iΓ6 sqrt(5) + 50)/10
Factor 2 from 50 + 6 i sqrt(5) giving 2 (3 i sqrt(5) + 25):
x = 1/102 (3 i sqrt(5) + 25) or x = (-6 i sqrt(5) + 50)/10
(2 (3 i sqrt(5) + 25))/10 = (2 (3 i sqrt(5) + 25))/(2Γ5) = (3 i sqrt(5) + 25)/5:
x = (3 i sqrt(5) + 25)/5 or x = (-6 i sqrt(5) + 50)/10
Factor 2 from 50 - 6 i sqrt(5) giving 2 (-3 i sqrt(5) + 25):
x = 1/5 (25 + 3 i sqrt(5)) or x = 1/102 (-3 i sqrt(5) + 25)
(2 (-3 i sqrt(5) + 25))/10 = (2 (-3 i sqrt(5) + 25))/(2Γ5) = (-3 i sqrt(5) + 25)/5:
Answer: x = 1/5 (25 + 3 i sqrt(5)) or x = (-3 i sqrt(5) + 25)/5
solved
general
10 months ago
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