Answer:
Step-by-step explanation:
2^2=1.75^2+3^2-2*3*1.75cos x
4=3.0625+9-10.5 cosx
10.5cos x=9-4+3.0625
10.5cosx=8.0625
cos x= 8.0625/10.5≈0.77
x≈40 degrees
 
        
                    
             
        
        
        
(4^-5)^3 =
4^(-5*3) =
4^-15 =
1/(4^15).....answer C
        
             
        
        
        
Firstly, put Derek and Paul's collection together:
1950, 1952, 1908, 1902, 1955, 1954, 1901, 1910, 1929, 1935, 1928, 1930, 1925, 1932, 1933, 1920
1950+1952+1908+1902+1955+1954+ 1901+1910+1929+1935+1928+1930+ 1925+ 1932+1933+1920
=30864
=30864÷16
=1929
∴the mean is 1929.
Median:
1901, 1902, 1908, 1910, 1920, 1925, 1928, 1929, 1930, 1932, 1933, 1935, 
1950, 1952, 1954, 1955
1930÷1929
=1.0005184
= Median
Range:
1955-1901
=54
∴the range is 54. 
        
                    
             
        
        
        
Answer:
2x +5y = -15
Step-by-step explanation:
We need to find the slope
m = (y2-y1)/(x2-x1)
    = (-7--1)/(10- -5)
    = (-7+1)/(10+5)
    -6/15
   -2/5
The point slope form
Y+7=
-2/5 (x - 10). 
Distribute
y + 7 = -2/5x + 4
Add 2/5 x to each side
2/5x +y +7 = 4
Subtract 7 from each side
2/5x +y = -3
Multiply each side by 5
5(2/5x +y) = -3*5
2x +5y = -15
This is standard form Ax + By = C where A is a positive integer