Пошаговое объяснение:
1.
1) -3 ∙( -20 + 8) =60-24=36
2)56 –2 ∙ (28 – 34) = 56-56+68=68
3) -6 (4 + а) + 3 (2а – 6) =-24-a+6a -18=-42+5a
2.
1) 3(х + 6) – х – 2(х + 9) =3x+18-x-2x-18=3x-x-2x+18-18=0
2) 6 – 3(х + 1) – (7 – х) =6-3x-3-7+x=6-3-7-3x+x=-4-2x
3) (8х + 3) – (10х - 6) – 9 = 8x+3-10x+6=-2x+9
4) 5 – 2(х - 1) – ( - 4 – х )= 5-2x+2+4+x=5+2+4-2x+x=11-x
5) (7х +1) – (9х + 3) + 5 = 7x+1-9x-3+5=7x-9x+1-3+5=-2x+3
6) (3,4 + 2у) - 7(у – 2,3) = 3,4+2y-7y+16,1=3,4+16,1-5y=19,5-5y
7) 4(5х + 2) - 10(3х - 3) + 15 = 20x+8-30x+30=20x-30x+8+30=-10x+38
8) 4(х - 1) - 2(2х - 8) + 12 = 4x-4-4x+16=4x-4x+16-4=12
9) 5,6 – 3(2 – 0,4х) - 0,4(4х - 1) = 5,6-6+1,2x-1,6x+0,4=5,6+0,4-6+1,2x-1,6x=-0,4x
10) 5(х - 12) + 6(х - 10) – (х - 1) = 5x-60+6x-60-x+1=5x+6x-60-60-x+1=11x-120+1-x=10x-119
Пошаговое объяснение:
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