1.
(4-7х)+5(1-х) = 4*15-3(2х+1),
4-7х+5-5х = 60-6х-3,
-7х-5х+6х = 60-3-4-5,
-6х = 48,
х = -8,
2.
(10-у)+2(3у+8) = 3(у+6),
10-у+6у+16 = 3у+18,
-у+6у-3у = 18-10-16,
2у = -8,
у = -4,
3.
4(3х+5)+5(9х-5) = 6*20+10(3х+1),
12х+20+45х-25 = 120+30х+10,
12х+45х-30х = 120+10-20+25,
27х = 135,
х = 5,
4.
(5-9х)-2(3+5х) = 4(5-3х),
5-9х-6-10х = 20-12х,
-9х-10х+12х = 20-5+6,
-7х = 21,
х = -3