We know that
sin²x+cos²x=1
so 
clear cos x
cos x=(+/-)√[1-sin²x]
in this problem
<span>Angle 0 is in quadrant 1 -----> cos o and sin o are positive
</span>sin o=2/5
cos x=√[1-(2/5)²]----> cos o=√[1-4/25]----> cos o=√[21/25]---> cos o=√21/5
the answer is
cos o=√21/5
        
             
        
        
        
9514 1404 393
Answer:
   translate 4 left and 3 up
Step-by-step explanation:
The value added to the x-coordinate is the translation to the right. Here, it is -4, so the translation is 4 units left.
The value added to the y-coordinate is the translation up. Here, it is +3, so the translation is 3 units up.
The rule effects a translation 4 units left and 3 units up.
 
        
             
        
        
        
The example on direct variation is illustrated below based on the information given. 
<h3>How to illustrate the direct variation?</h3>
An example will be:
When x = 2, y = 10. Find the value of y when x is 6. 
In this case, this will be calculated thus:
y = kx
10 = 2k
k = 10/2
k = 5
Since y = kx.
y = 5 × 6
y = 30
The value of y is 30.
Learn more about variation on:
brainly.com/question/25215474
#SPJ1
 
        
             
        
        
        
Steps to solve:
25 = x + 19
~Subtract 19 to both sides
6 = x
Best of Luck!
 
        
                    
             
        
        
        
The formula for arc length is s=r*angle theta where s is the arc length, r is the radius, and angle theta is central angle formed by the arc in radians. 
In this case, the angle would be s/r or 4.2/4  which is 1.05 radians. We have to convert this into degrees and so you would multiply 1.05 by (180/pi) which results in approximately 60 degrees. Remember, if you want to convert radians into degrees, the conversion factor is 180/pi and for degrees into radians, it is pi/180.