Toán Lớp 6: -12-(x-4)^2=-76

Question

Toán Lớp 6:  -12-(x-4)^2=-76                                                                                                                                                                                     mong mọi người giải nhanh giúp em

haiyemy · Answer

-12-(x-4)^2=-76       (x-4)^2=(-12)-(-76)       (x-4)^2=64       (x-4)^2=(+-8)^2       => ( left[  begin{array}{l}x-4=8  x-4=-8 end{array}  right. )        => ( left[  begin{array}{l}x=12  x=-4 end{array}  right. )        Vậy x in{12;-4}

ngocbichchau · Answer

- 12 - ( x - 4 )^2 = - 76   &rArr; ( x - 4 )^2 = - 12 - ( - 76 )   &rArr; ( x - 4 )^2 = 64   &rArr; $ left[ begin{matrix}( x - 4 )^2 = 8^2  ( x - 4 )^2 = ( - 8 )^2 end{matrix} right.$   &rArr; $ left[ begin{matrix} x - 4 = 8  x - 4 = - 8 end{matrix} right.$   &rArr; $ left[ begin{matrix} x = 12   x = - 4 end{matrix} right.$   Vậy , x &isin; { 12 ; - 4 } .