Answer:
<h2>
 63mm/min</h2>
Step-by-step explanation:
Area of a triangle = 1/2 * base * height
A = 1/2bh
Rate of change of area is expresssed as dA/dt = dA/db * db/bt
db/dt is the rate at which the base is increasing.
Given db/dt = 18mm/min
A = 1/2*7b
A = 7b/2
dA/db = 7/2
The rate at which the area is changing dA/dt = dA/db * db/bt
dA/dt = 7/2 * 18
dA/dt = 7*9
dA/dt = 63mm/min
<em>Hence the rate at which the area of the triangle is changing is  63mm/min </em>
 
        
             
        
        
        
Answer:
Total area is 198.6cm²
Step-by-step explanation:
This problem bothers on the mensuration of flat shapes. 
Step one 
From the given figure the two semi circles left and right can be resolved as a whole (a complete circle) with diameter d 10cm
Radius r = 10/2= 5cm
Area of circle A= πr²
A= 3.142*5²
A= 3.142*25
A= 78.55
A= 78.6cm²
Step two 
The remaining part of the shape is a rectangle with length (22-10)= 12cm
I.e the 10 is as a result of the radius of the two semi circles = r+r= 5+5=10
The rectangle has a width of 10cm
Area of rectangle A=12*10= 120cm²
Hence the total surface area of the shape 
Total area = 120+78.6
Total area = 198.6cm²
 
        
             
        
        
        
I am sorry it’s to hard I tried this about 5x sorry bro
        
             
        
        
        
 Point L is the midpoint 
 
The midpoint is halfway between the two points. In this case, Point F and Point B are 10 units away from each other. The midpoint is the distance between the points (10) divided by 2.