Think of the 13-ft length of the ladder as the hypotenuse of a right triangle. Represent the horiz. distance from foot of ladder to base of tree by x, or 5 ft.
Represent the vert. dist. from base of tree to top of ladder by y, which is unknown.
Then (13 ft)^2 = (5 ft)^2 + y^2, or
 169 ft^2 = 25 ft^2 + y^2. This simplifies to y^2 = 144. Thus y = + 12 feeet.
Note: Please pay attention to your spelling: "lader i up agenst a tree" should be "the top of a 13-ft ladder is placed against a tree."
 
        
             
        
        
        
= x^2 - y^2/6 * 12/(x-y)
= 6x^2 -y^2 * 72/(x-y)
= 6x^2(x-y) -y^2(x-y) * 72
= 6x^3 - 18x^2 -xy^2 + y^3 * 72
= 432x^3 - 1296x^2 -72xy^2 + 72y^3 
        
             
        
        
        
Answer:
She increased 80% the practise time
Step-by-step explanation:
The question is incomplete, the following is missing:
<em>by how much did she increase the time she practised each day?
</em>
From Monday to Wednesday she increased 90 - 50 = 40 minutes  the practise time.
To compute the increment as a percentage use: increment/reference *100
In this case, that is: 40/50*100 = 80%, where 50 minutes is taken as a reference.
 
        
                    
             
        
        
        
Your answer is going to be odd