Question

Determine o Valor de X Em .
A) 5+Cx,2=x+14
B) Cx+3,2=15

Answer 1

A) 5 + x!/2!.(x-2)! = x + 14
    x.(x-1).(x-2)!/ 2.1!.(x-2)! = x + 14 - 5
    x.(x-1)/2 = x + 9
    x² - x = (x+9) . 2
    x² - x = 2x + 18
    x² - 3x - 18 = 0
Com a fórmula de bhaskara x = 6.

B) (x+3)!/2!.(x+3+2)! = 15
    (x+3)!/2.1!.(x+1)! = 15
    (x+3).(x+2).(x+1)!/2.1!.(x+1)! =15
    x²+2x+3x+6 = 15.(2)
    x²+5x+6-30=0
    x²+5x-24=0
Com a fórmula de bhaskara x = 3