Answer:
Its the 3 one
Step-by-step explanation:
Answer:
2x^2 = 6x - 5.
-x^2 - 10x = 34.
These have only complex roots/
Step-by-step explanation:
3x^2 - 5x = -8
3x^2 - 5x + 8 = 0
There are complex roots if the discriminant 9b^2 - 4ac) is negative.
Here the discriminant D = (-5)^2 - 4*-5*8 = 25 + 160
This is positive so the roots are real.
2x^2 = 6x - 5
2x^2 - 6x + 5 = 0
D = (-6)^2 - 4*2*5 = 36 - 40 = -4
So this has no real roots only complex ones.
12x = 9x^2 + 4
9x^2 - 12x + 4 = 0
D = (-12)^2 - 4*9 * 4 = 144 - 144 = 0.
- Real roots.
-x^2 - 10x = 34
x^2 + 10x + 34 = 0
D = (10)^2 - 4*1*34 = 100 - 136 = -36.
No real roots = only complex roots.
Answer:
f
(
2
)
=
20
Explanation:
To evaluate f
(
2
)
substitute x = 2 into f
(
x
)
f
(
2
)
=
(
×
2
2
−
(
4
×
2
×
x
=
28−
8
=
20
Answer:
Rational
Step-by-step explanation:
1.256 is not a whole #, and it's also not an integer. An integer is basically whole #s and their opposites. The # is not irrational. 1.256 is a terminating decimal, and can be turned into a fraction. 1.256 = 1 32/125.