6. Point (4, 1) lies on the line:
(a) x + 2y = 5 (b) x + 2y = -6
(c) x + 2y = 6
(d) x + 2y = 16
Answers
Answer:
the coorect answer is C
Answer:
Step-by-step explanation:
The height of the poles are 30√3 feet and 60√3 feet.
Step-by-step explanation:
Referring to the figure attached below, let's make some assumptions
AB = h₁= height of the first pole
ED = h₂ = height of the second pole
BD = distance between the two poles = 90 feet
Angle of elevation from point C to the top of AB = θ₁ = 60°
Angle of elevation from point C to the top of ED = θ₂ = 60°
Let the distance of point C from the foot of AB be “BC”, then the distance of point C from the foot of ED will be “CD = (90 - BC)”.
Since it is given that the ratio of the heights of the pole are 1:2
So, if the height of the first pole AB is “h1” then the height of the second pole ED will be "h2 = 2h1”.
Now,
Consider ΔABC, applying the trigonometric ratios of a triangle, we get
tan θ₁ = perpendicular/base
⇒ tan 60° = AB/BC
⇒ √3 = h₁/BC
⇒ h₁ = BC√3 ...... (i)
and,
Consider ΔEDC, applying the trigonometric ratios of a triangle, we get
tan θ₂ = perpendicular/base
⇒ tan 60° = ED/CD
⇒ √3 = h₂/(90 - BC)
⇒ 2h₁ = √3 [90 - BC]
⇒ h₁ = (√3/2) [90 - BC] ...... (ii)
From (i) & (ii), we get
BC√3 = (√3/2) [90 - BC]
⇒ 2BC = 90 – BC
⇒ 2BC + BC = 90
⇒ 3BC = 90
⇒ BC = 90/3
⇒ BC = 30
Substituting the value of BC in (i), we get
h₁ = BC√3 = 30√3 feet ← height of the first pole
∴ h₂ = 2 * h₁ = 2 * 30√3 = 60√3 feet ← height of the second pole