Four less than the square of a number

x² - 4

Four less than the square of a number

       ↓                                   ↓

(Take away 4)                     x²

Four less than the square of a number = x² - 4

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47

the correct option is b

step-by-step explanation: