SOLUTION: i do not knwo how to solve this can some one please assist me thank you 52. 2y^2 – 3y – 6 = 0 real and imaginary solutions to each equation. 104. x^-2 – 9x^-1 + 18 = 0

Algebra ->  Roman-numerals -> SOLUTION: i do not knwo how to solve this can some one please assist me thank you 52. 2y^2 – 3y – 6 = 0 real and imaginary solutions to each equation. 104. x^-2 – 9x^-1 + 18 = 0       Log On


   

Question 60559: i do not knwo how to solve this can some one please assist me thank you
52. 2y^2 – 3y – 6 = 0
real and imaginary solutions to each equation.
104. x^-2 – 9x^-1 + 18 = 0
not sure if you solve them both the same way or not i have a hard time recognizing which way to solve problems. thank you
Found 2 solutions by jai_kos, FadelSalem:
Answer by jai_kos(139) About Me  (Show Source):
You can put this solution on YOUR website!
First check whether in the quadratic form, then use the formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Where a = 2, b = -3 and c = -6
Substitute the above the formula, we get
x+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2-4%2A2%2A-6+%29%29%2F%282%2A4%29+
x+=+%283%2B-+sqrt%289%2B+48+%29%29%2F%284%29+
x+=+%283%2B-+sqrt%2857%29%29%2F%284%29+

x^-2 – 9x^-1 + 18 = 0
Multiply the equation with x^2
x^2 * x^-2 – x^2 * 9x^ -1 + x^2 *18 = 0
1 – 9x + 18x^2 = 0
Rearrange the above, we get
18x^2 – 9x + 1 =0
Use the formula,
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
Where a = 18, b = -9and c = 1
Substitute the above the formula, we get
x+=+%28-%28-9%29+%2B-+sqrt%28+%28-9%29%5E2-4%2A18%2A+6+%29%29%2F%282%2A+18%29+
x+=+%289+%2B-+sqrt%28+81-4%2A18%2A+6+%29%29%2F%282%2A+18%29+
x+=+%289+%2B-+sqrt%2881-+432+%29%29%2F%2836%29+
x+=+%289+%2B-+sqrt%28-351%29%29%2F%2836%29+

Answer by FadelSalem(12) About Me  (Show Source):
You can put this solution on YOUR website!
2y^2 – 3y – 6 = 0
Use the formula: x = [-b + - sqt(b^2 - 4 ac)]/2a
y = [3 +or- sqt(9 + 48)]/4 = [3 +-sqrt 57]/4
................................
x^-2 – 9x^-1 + 18 = 0
(x^-1 -3)(x^-1 -6) = 0
x^-1 =3 or x^-1 = 6
so, x = 1/3 or x = 1/6
Happy New Year
Fadel Salem - Egypt
fadelsalem@hotmail.com