a. 2 real, rational
b. 2 real, irrational
c. 2 complex
d. 1 real, rational
2007-01-27 10:45:28 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
2x^2 - 7x + 9 = 0
The discrimination, by definition, is the value of b^2 - 4ac.
You're going to have 3 possible solutions:
1) Negative number. In this case, we have 2 complex roots.
2) 0. In this case, we have 1 real rational root.
3) Positive number.
a) Perfect square: two rational roots.
b) Not a perfect square: two irrational roots.
Note that ax^2 + bx + c = 0 is the form of our quadratic. That means in our case,
a = 2, b = -7, c = 9, so
b^2 - 4ac = (-7)^2 - 4(2)(9) = 49 - 72 = -23.
This is obviously a negative number, so we have two complex roots.
2007-01-27 10:51:04 · answer #1 · answered by Puggy 7 · 1⤊ 0⤋
2^
7x+9
2x^2=-7
2x-#=-9
= 2 before negetive number x 2 equale zero but all number 2 x 2 ^
would equal depending on negetive seven ^ negetive number plus switch 2 for uneven number equals negetive 9. 7 x plus nine 7 times easy equation of ruled out number cant mutiply a negetive first rule +9 equals equation -9 plus 9 equals zero
2007-01-27 18:59:05 · answer #2 · answered by j.b 2 · 1⤊ 0⤋
Use this formula for discriminants:
b^2-4ac
a=2,b=-7,c=9
(-7)^2-4((2)(9))
49-4(18)
49-72
-23
The answer is c.
2007-01-27 18:52:32 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Discriminant = b^2-4ac=49-72= -23
Thus the discriminant is <0, then theres two complex answers...C...
Cheers
2007-01-27 18:51:28 · answer #4 · answered by Anonymous · 1⤊ 0⤋
b^2-4(a)(c)
(-7)^2-4(2)(9)
49-72
-23
C. 2 complex
2007-01-27 18:50:40 · answer #5 · answered by 7 · 1⤊ 0⤋