In order for me to begin an answer, you must tell me something about the relationship
between 'x' and 'y'. A simple linear equation would have helped immensely. As it is,
there's nothing I can do.
13 ? 15
If you mean: x^2+15-3x then its value is 19 when x equals 4
It is 36
15
It is: 36
-15 + 4 = -11
x = sin-1 (4/15) ( sin -1 is [SHIFT] [sin] on a calculator ) = 15.5
72
4
It is: 28-4-9 = 15
3.75 x 4 = 15
If you mean: 7/8b - 1 = -15/16b + 4 Then the value of b works out as 0.3625