Answer:
Step-by-step explanation:
Split the trapezoid as pictured below
Find its height and the upper base, then find the area of the trapezoid.
There are 3 pieces, two of them are 45°×45° and 30°×60°×90° triangles
- The ratio of sides of a 30°×60°×90° triangle is 1 : √3 : 2
- The legs of a 45x45 triangle are equal
<u>The above mentioned properties give us:</u>
- h = 16/2 = 8 m
- b = 8√3 ≈ 13.85 m
- a = h = 8 m
<u>Now find the area:</u>
- A = 1/2( 13 + 8 + 13.85 + 13)*8 = 191.4 m²
Correct choice is B
1/7 is your answer. It can't be reduced any further. If there is supposed to be a problem, next time, add it.
Answer:
Let the speed of the train be x km/h.
Case 1:
Distance = 288 km
Speed = x km/h
Time = Distance/Speed
= 288/x h
Case 2:
Distance = 288 km
Speed = (x+4) km/h
Time = 288/x + 4 h
Since 288/x > 288/x + 4
288/x - 288/x+4 = 1
288[1/x - 1/x+4 ] = 1
[ x + 4 - x / x(x + 4) ] = 1/288
[4 / x^2 + 4x ] = 1/288
x^2 + 4x = 1152
x^2 + 4x - 1152 = 0
x^2 + 36x - 32x - 1152 = 0
x(x + 36) - 32(x + 36) = 0
(x + 36)(x - 32) = 0
x + 36 = 0 , x - 32 = 0
x = -36 , x = 32
x = -36 , rejected since speed cannot be negative.
Therefore , speed of the train = 32 km/h
Answer:
The inside of the pentagon and the angle outside the pentagon can add up the the angle of 180 degrees.
Step-by-step explanation:
