1) -40*(-7х+5)=-1600 2)2,1*(4-6а)=-42 3)(-20х-56)*2 =106 4)-3(2-15х)=-6 5)5*(13-2х)=-19-3х 6)7*(28-3х)=-2-3х 7)3*(4-5х)=4х-26 8)

<span>-40*(-7х+5)=-1600
280x-200=-1600
280x=-1600+200
280x=-1400
x=-1400:280
x=-5
===================
</span>2,1*(4-6а)=-42
8,4-12,6a=-42
-12,6a=-42-8,4
-12,6a=-50,4
a=-50,4:-12,6
a=4
================
<span>(-20х-56)*2 =106
-40x-112=106
-40x=106+112
-40x=218
x=218:-40
x=-5,45
=================
</span>-3(2-15х)=-6
-6+15x=-6
15x=-6+6
15x=0
x=0
=============
<span>5*(13-2х)=-19-3х
65-10x=-19-3x
-10x+3x=-19-65
-7x=-84
x=-84:-7
x=12
==============
</span>7*(28-3х)=-2-3х
196-21x=-2-3x
-21x+3x=-2-196
-18x=-198
x=-198:-18
x=11
===================
<span>3*(4-5х)=4х-26
12-15x=4x-26
-15x-4x=-26-12
-19x=-38
x=-39:-19
x=2
========================
</span><span>(-7х+15)*11=-78+4х </span>
-77x+165=-78+4x
-77x-4x=-78-165
-81x=-243
x=-243:-81
x=3
======================

1)280x=-1400
X=0,5
2)8,4-12,6a=-42
-12,6a=-50,4
A=4
3)-40x-112=106
-40x=218
X=-5,45