Answer:
see explanation
Step-by-step explanation:
The perimeter is the sum of the 3 sides, that is
perimeter = 8 + 12 + 17 = 37 cm
To use Heron's formula for area (A)
A = 
where a, b and c are the lengths of sides and s the semi perimeter
s = 37 ÷ 2 = 18.5
let a = 8, b = 12 and c = 17, then
A = 
    = 
    =  ≈ 43.52 cm² ( to 2 dec. places )
 ≈ 43.52 cm² ( to 2 dec. places )
 
        
                    
             
        
        
        
Answer:
38
Step-by-step explanation:
Follow orders of operations. 
Slove the expression in the parenthesis or brackets whatever, same thing.
5*6=30
Now add 
30+8=38
 
        
                    
             
        
        
        
Answer:
Asa
Step-by-step explanation:
Because if u look left to right on one triangle there is a angle and in between they have a com on line and on the right theres another angle so There for it’s angle side angle 
 
        
             
        
        
        
Answer:
 
Step-by-step explanation:
 The formula that is used to calculate the area of a rectangle is:
 
 Where "l" is the lenght and "w" is the width.
 You know that the area of that rectangle is:
 
 And, according to the exercise, its lenght is 7 more than its width; then:
 
 Then, you can make the corresponding substitution into the formula  :
:
  
 Simplify:
 
 Factor the equation. Find two numbers whose sum is 7 and whose product is -744. These are 31 and -24. 
 Then, you get:
 
 The width of the rectangle is the positive value:
 
 Then, the lenght is:
 