Question

Efectuati :
a ) (12x15-15)+5x{24-5x[19-2x(17-4x2]}

b ) 5+2x{3+2x[5+5x(5x1-1)]}

c ) [50-3x(11x9-12x7)]x{2+4[8+5x(3+3x7)]}

d ) {[9x7-17+2x8}2-123}+[55-16x(24-21)]x2

Answer 1

a) (12x15-15)+5x{24-5x[19-2x(17-4x2]}=
= 11x15+5x{24-5x[19-2x(17-8]}=
= 165+5x[24-5x(19-2x9)]=
= 165+5x19=
=165+95=260

b) 5+2x{3+2x[5+5x(5x1-1)]}=
= 5+2x[3+2x(5+5x4)]=
= 5+2x(3+2x25)=
= 5+2x53=
=5+106=111

c) [50-3x(11x9-12x7)]x{2+4[8+5x(3+3x7)]}=
= [50-3x(99-84)]x[2+4(8+5x24)]=
= (50-3x15)x(2+4x128)=
= (50-45)x(2+512)=
= 5x514=
=2570

d) {[9x7-17+2x8}2-123}+[55-16x(24-21)]x2=
= {[63-17+16}2-123}+(55-16x3)x2=
=(62x2-123)+(55-48)x2=
=(124-123)+7x2=
=1+14=15