Answer:
Step-by-step explanation:
3 3/8 = ((3×8)+3)/8= 27/8
Step-by-step explanation:
25 questions, 2 points each.
that means there were 25×2 = 50 points in total.
Gideon got 42 out of the 50.
100% = 50
1% = 100%/100 = 50/100 = 0.5
42 is how many % ? as many as 1% (0.5) fits into 42.
so,
42/0.5 = 42×2 = 84%
he scored 84%.
Answer:
The correct option is C.
C) ellipse, -30°
Step-by-step explanation:
General form of equation for a conic section is:
(A)x² + (B)xy + (C)y² + (D)x + (E)y + F = 0
The equation of the conic section is given:
21x² - (8√3)xy + 13y² = 225
21x² - (8√3)xy + 13y² - 225 = 0
Which can be rewritten as:
(21)x² + (-8√3)xy + (13)y² + (0)x + (0)y + (-225) = 0
where
A = 21
B = -8√3
C = 13
D = 0
E = 0
F = -225
Consult the table below.
As A ≠ C and and AC > 0 , the equation represents an ellipse
The angle of rotation can be found by following equation:
cot(2θ) = (A - C)/B
cot(2θ) = (21 - 13)/(-8√3)
2θ = cot⁻¹(8/-8√3)
2θ = 120°
θ = 60° (from x-axis)
As the major axis of ellipse lies on y-axis, axis of rotation from y-axis is
θ = -30°