Answer: the speed of the wind is 1.5 mph
Step-by-step explanation:
Let x represent the speed of the wind.
Time = distance/speed
Craig can ride his bike at an average rate of 14 miles per hour in calm air. Traveling with the wind, his total speed would be (14 + x) mph
Time taken to travel 62 miles with the wind would be
62/(14 + x)
In the same amount of time it took him to ride 50 miles against the wind. His total speed would be
(14 - x) mph. Time taken to travel 50 miles is
50/(14 - x)
Since the time is the same, then
62/(14 + x) = 50/(14 - x)
Cross multiplying, it becomes
62(14 - x) = 50(14 + x)
868 - 62x = 700 + 50x
- 62x - 50x = 700 - 868
- 112x = - 168
x = - 168/-112
x = 1.5
You can understand this by two ways
1) through congruency rules
It says that triangle ABE is congruent to DCE
So the corresponding angles are equal
Eg
Angle A to Angle D
Angle B to angle C
Angle E to angle E
So they’re asking the angles AEB and DEC (which are equal as per congruency)
Thus you can equate them
4y-15=69
y=21
2) through vertically opposite angles
Since the triangles’ angles are vertically opposite one another, they are equal.
Then you can equate them the same way
Hope this helped!!
Right format of question:
Plot two points that are 7 units from Point D and also share the same x-coordinate as Point D.
Answer:
and
Step-by-step explanation:
Given
Required
Determine a point 7 points from D and in the same x coordinate
Represent this point with D'.
From the requirement of the question, D' has two possible values and these values are:
----> 7 units down and
----> 7 units up
Substitute values for x and y in and
So, we have:
Answer:
we know surface area=pi*d*h=3.14*8*5=125.6sqm
Answer:
36 White cars
Step-by-step explanation:
total of 40 white cars and yellow cars" means 40 = W + Y
"9 times as many white cars as yellow cars" means 9Y = W
9W + 9Y = 360 (first equation; multiply (W+Y=40) by 9 to eliminate Y)
W - 9Y = 0 (carefully revise the second equation)
------------------- (Elimination method: add the equations)
10W = 360
W = 36 Ans: 36 White cars
Checking (very important):
40 = W + Y
40 = 36 + Y
4 = Y
is 9(4) = 36
36 = 36