Answer:
DF= should be 30
Step-by-step explanation:
Question 1:
(a) Using sine rule
ground/Sin 49 = plank/Sin 90
But sine 90 = 1, ground = 3 ft
Then,
3/Sin 49 = plank
Length of the plank = 3/Sin 49 ≈ 4.0 ft (rounded to nearest tenth)
(b) Height where the plank touches the wall
wall = Sqrt (plank^2 - ground^2) = Sqrt (4.0^2 - 3.0^2) ≈ 2.6 ft (Rounded to nearest tenth)
Question 2:
(a) Angle x
ground = 24 ft
support wire = 30 ft
Applying sine rule
support wire/Sin 90 = ground/Sin (90-x) ----- but Sin 90 = 1
Then,
Support wire = ground/Sin (90-x)
Sin (90-x) = ground/support wire = 24/30 = 0.8
90-x = Sin^-1(0.8) = 53.13 => x = 90-53.13 = 36.9°
(b) Height where the wire touches the tree (tree)
tree = Sqrt (support wire^2 - ground^2) = Sqrt (30^2 - 24^2) = 18 ft
Answer:
¿Qué significa esto porque no entiendo?
Step-by-step explanation:
<em>Answer: </em><u><em>
The perpendicular distance between the two parallel sides of a trapezium is known as the height of a trapezoid. In simple words, the base and height of a trapezoid are perpendicular to each other. The trapezoids can be both right trapezoids (two 90-degree angles) and isosceles trapezoids (two sides of same length).</em></u>
Answer:
a = -3 and b=5
Step-by-step explanation:
Given that 10 can be written as 2*5 or √2*√2*5, and √18 can be written as √(2*9) or √2*√9 or 3√2, you can write the fraction as:
![\frac{5\cdot\sqrt2\cdot\sqrt2-3\sqrt2}{\sqrt2}](https://tex.z-dn.net/?f=%5Cfrac%7B5%5Ccdot%5Csqrt2%5Ccdot%5Csqrt2-3%5Csqrt2%7D%7B%5Csqrt2%7D)
So getting rid of the √2 factor, you get 5√2 - 3, so a=-3 and b=5