Question

-20-5x [(-2) x (4-7)+8-2x5]

Answer 1

-20-5×[(-2)×(4-7)+8-2×5]=
-20-5×[(-2)×(-3)+8-2×5]=
-20-5×[6+8-2×5]=
-20-5×[14-2×5]=
-20-5×[14-10]=
-20-5×[4]=
-20-5×4=
-20-20=
-40

Espero ter ajudado