Answer:
1)65.9
2)326.6
3)13.6
4)8.0
Step-by-step explanation:
The trick is always to look at the number after the first decimal for rounding to 1 decimal place, if its above 5, you round it up to the next decimal; eg. 13.45 = 13.5 because the 5 will round it up,and if value below 5, you round it down; eg. 12.34 = 12.3 because the 4 is below 5 and the nearest 10th decimal is 3.
 
        
                    
             
        
        
        
Answer:
Dvfgghytjyjt
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
Below
Step-by-step explanation:
Let D be the diagonal of this square.
D forms with AB and BC a right triangle where D is the hypotenus.
We will apply then the Pythagorian theorem
●The Pythagorian theorem
● D^2 = AB^2 + BC^2 
ABCD is a square, so AB=BC 
● D^2 = AB^2 + AB^2 
● D^2 = 2AB^2 
We khow that is D= 5 cm
● 25 = 2AB^2 
● 25/2 = AB^2 
● 5/√2 = AB 
AB is 5√2 cm
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The perimeter is:
● P = 4AB
● P = 4×(5/√2)
● P = 20/√2 
● P = 10×2/√2
● P = 10√2 cm
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The area is
● A = AB^2 
● A = (5/√2)^2
● A = 25/2 cm^2 
 
        
                    
             
        
        
        
Answer:
see explanation
Step-by-step explanation:
Using the Addition/ Subtraction formulae for cosine
Consider the left side
cos(x - y) - cos(x + y)
= cosxcosy + sinxsiny - (cosxcosy - sinxsiny) ← distribute
= cosxcosy + sinxsiny - cosxcosy + sinxsiny ← collect like terms
= 2sinxsiny = right side ⇒ proven