Discriminant = b^2 - 4ac, where a, b and c come from the form of the quadratic equation as ax^2 + bx + c
Discriminant = (4)^2 - 4(1)(5)
= 16 - 20
= -4
-4 < 0, therefor there are no roots
(If the discriminant = 0, then there is one root
If the discriminant > 0, there are two roots, and if it is a perfect square (eg. 4, 9, 16, etc.) then there are two rational roots
If the discriminant < 0, there are no roots)
Answer:
Step-by-step explanation:
Length = L.
Width = 2L-3.
A = L * W = 170.
L * (2L-3) = 170.
2L^2 - 3L - 170 = 0,
L = (-B +- Sqrt(B^2-4AC))/2A.
L = (3 +- Sqrt(9 + 1360))/4,
L = (3 +- 37)/4 = 0.75 +- 9.25 = 10, and -8.5. In.
Use positive value: L = 10 In.
Answer:
y = - 10
Step-by-step explanation:
Given that y varies directly with x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = 2 when x = - 4, that is
2 = - 4k ( divide both sides by - 4 )
= k, that is
k = -
y = - x ← equation of variation
When x = 20, then
y = - × 20 = - 10
Answer: The answer is (B) ∠SYD.
Step-by-step explanation: As mentioned in the question, two parallel lines PQ and RS are drawn in the attached figure. The transversal CD cut the lines PQ and RS at the points X and Y respectively.
We are given four angles, out of which one should be chosen which is congruent to ∠CXP.
The angles lying on opposite sides of the transversal and outside the two parallel lines are called alternate exterior angles.
For example, in the figure attached, ∠CXP, ∠SYD and ∠CXQ, ∠RYD are pairs of alternate exterior angles.
Now, the theorem of alternate exterior angles states that if the two lines are parallel having a transversal, then alternate exterior angles are congruent to each other.
Thus, we have
∠CXP ≅ ∠SYD.
So, option (B) is correct.