1/4 of 52 = 13.
you didn't list the options....
X - y = 9
x + 2y = 27
You can subtract the top equation from the bottom
3y = 18
y = 6
x = 15
The two numbers are 15 and 6
Answer=1.335 or 1 67/200
813 field goals
1422 attempts
1422-813=609 fails
813/609=1.335 successes per fail
1.335= 1 335/1000= 1 67/200
The identity in question is
cos(a - b) = cos(a) cos(b) + sin(a) sin(b)
so that
cos(a - b) = 12/37 cos(a) + 3/5 sin(b)
Since both a and b lie in the first quadrant, both cos(a) and sin(b) will be positive. Then it follows from the Pythagorean identity,
cos²(x) + sin²(x) = 1,
that
cos(a) = √(1 - sin²(a)) = 4/5
and
sin(b) = √(1 - cos²(b)) = 35/37
So,
cos(a - b) = 12/37 • 4/5 + 3/5 • 35/37 = 153/185