Question

In a class of 22 students, number of girls is 50 less than square of numbers of boys.
find the number of girls​

Answer 1

Answer:

let number of boys be x.

so number of girs =

${x}^{2} - 50 \\ according \: to \: question \\ total \: students = 22 \\ x + {x}^{2} - 50 = 22 \\ {x}^{2} + x - 72 = 0 \\ {x}^{2} + 9x - 8x - 72 = 0 \\ x(x + 9) - 8(x + 9) = 0 \\ (x + 9)( x - 8) = 0 \\ x = - 9 \: or \: x = 8$

hence number of boys = 8 and number of girls =14