Share
solve for x to the nearest tenth y completing the square: x^2-5x+7=0
Question
solve for x to the nearest tenth y completing the square: x^2-5x+7=0
in progress
0
Mathematics
1 year
2021-09-03T20:55:15+00:00
2021-09-03T20:55:15+00:00 2 Answers
2 views
0
Answers ( )
Answer:
x = (1/2)(5 ± i√3)
Step-by-step explanation:
x² – 5x + 7 = 0
subtract 7 from both sides
x² – 5x = -7
Use half the x coefficent, -5/2, as the complete the square term
(x – 5/2)² = -7 + (-5/2)²
(x – 5/2)² = -7 + 25/4
(x – 5/2)² = -3/4
Take the square root of both sides
x – 5/2 = ±(√-3) / 2
x – 5/2 = ±(i√3) / 2
Add 5/2 to both sides
x = 5/2 ± (i√3) / 2
factor out 1/2
x = (1/2)(5 ± i√3)
Answer:
does not have a solution because √-0.75 ≠ R
Step-by-step explanation:
x^2 – 5x + (5/2)^2 = -7
x^2 – 5x + 6.25 = -7 + 6.25
(x – 2.5)^2 = -0.75
(x – 2.5) = √-0.75
does not have a solution because √-0.75 ≠ R