Step-by-step explanation:
the angle CDB is the supplementary angle to 9x+10 (angle ADC).
that means they stand together for 180°. as all angles around a single point on one side of a line are together always 180°.
and then, the sum of all angles in a triangle is always 180°.
so,
CDB + (4x + 10) + 50 = 180
CDB = 180 - (9x + 10) = 180 - 9x - 19 = 170 - 9x
therefore, 
(170 - 9x) + (4x + 10) + 50 = 180
170 - 9x + 4x + 10 + 50 = 180
-5x = -50
5x = 50
x = 10
angle CDB = 170 - 9x = 170 - 90 = 80°
 
        
             
        
        
        
Answer: 8 > u > 6. I hope it helps!
 
        
             
        
        
        
Answer:
x = 12
Step-by-step explanation:
We have a right triangle with hypotenuse 10 and the height 8.  Either the one on the left or the one on the right
We can find the base using the Pythagorean theorem
a^2 + b^2 = c^2 
a^2 +8^2 = 10^2
a^2  +64 = 100
Subtract 64 from each side
a^2 = 100 -64
a^2 = 36
Take the square root of each side
a = 6
Now a is 1/2 of the total base of the big triangle.  It is identical since the triangles are equal
x = 2 * a
x = 2*6 = 12
 
        
                    
             
        
        
        
Answer:
oh, you may have forgotten to add the file, you can edit and add it, which i will edit my response and respond.
Step-by-step explanation:
 
        
             
        
        
        
Answer:
525 x 1,050
A = 551,250 m²
Step-by-step explanation:
Let 'L' be the length parallel to the river and 'S' be the length of each of the other two sides.
The length of  the three sides is given by:

The area of the rectangular plot is given by:

The value of 'S' for which the area's derivate is zero, yields the maximum total area:

Solving for 'L':

The largest area enclosed is given by dimension of 525 m x 1,050 and is:
