Speed traveling west = x - 10 km /hr
275 / ( x-10) - 300 / x = 1/2
275 *2x - 300 (x-10)*2 = ( x-10) *x
550x - 600x +6000 = x^2 -10x
x^2 +40x - 6000 = 0
( x -60) ( x+100) = 0
x = 60
ANSWER East = 60 km/ hr West = 50 km /hr
CHECK
300 /60 = 5 hours
275 /50 = 5.5 hours
Solve for x over the real numbers:
x^2 - 4 x = 5
Subtract 5 from both sides:
x^2 - 4 x - 5 = 0
x = (4 ± sqrt((-4)^2 - 4 (-5)))/2 = (4 ± sqrt(16 + 20))/2 = (4 ± sqrt(36))/2:
x = (4 + sqrt(36))/2 or x = (4 - sqrt(36))/2
sqrt(36) = sqrt(4×9) = sqrt(2^2×3^2) = 2×3 = 6:
x = (4 + 6)/2 or x = (4 - 6)/2
(4 + 6)/2 = 10/2 = 5:
x = 5 or x = (4 - 6)/2
(4 - 6)/2 = -2/2 = -1:
Answer: x = 5 or x = -1
The answers are as follows:
1. Triangles are often used to build different types of support structures because of its beneficial properties. Triangles is rigid in shape and it has strength. When force is applied to the side of a triangle, it can not shift into another shape, this is because its sides and angles are fixed.
2. The properties of triangle that make it a desirable geometric shape for building support structures is its fixed sides, fixed angles, rigidity and strength. Triangles are the strongest shapes and they are stable. Thus, triangle can be easily fix together to provide strength and stability over a wide area.
3. There are different types of triangles, these include: equilateral triangle, scalene, isosceles, right triangle, obtuse and acute. Of all these triangles, the best triangle is equilateral triangle.
4. Triangle is preferred over other types of polygon because, it is the strongest. The other polygons can be bent into different other forms that are not regular polygon, but a triangle always retains its shape and can not be deformed.
After 20 minutes Clint is on page = 151
After 45 minutes Clint is on page = 181
Time slot = 
minutes
Difference in pages in 25 minutes = 
pages.
Lets suppose Clint is reading each page at same pace.
So , In 25 minutes, he can read = 30 pages
In 1 minute he can read = 
pages
Initial time is 20 minutes, so he can read the number of pages in 20 minutes = 
So, number of pages Clint read prior to study hall were =
pages.
