1) (2x + 1) × (x - 3) - (1 - 3) × (x - 5) = 29 - 11x
2x² - 6x + x - 3 - (x - 5 - x² + 5x) = 29 - 11x
2x² - 6x + x - 3 - (6x - t - x²) = 29 - 11x
2x² - 6x + x - 3 - 6x + 5 + x² = 29 - 11x
3x² - 11x + 2 = 29 - 11x
3x² + 2 = 29
3x² = 29 - 2
3x² = 27
x² = 9
x = ± 3
x¹ = 3
x² = - 3
2) (3x - 8)² - (4x - 6)² + (5x - 3) × (5x + 3) = 96
9x² - 48x + 64 - (16x² - 48x + 36) + 25x² - 4 = 96
9x² - 48x + 64 - 16x² + 48x - 36 + 25x² - 4 = 96
18x² + 24 = 96
18x² = 96 - 24
18x² = 72
x² = 4
x = ± 2
x¹ = 2
x² = - 2
3) (x - 2) × (x² + 2x + 4) - x² × (x - 18) = 0
x³ - 8 - x³ + 18x² = 0
- 8 + 18x² = 0
18x² = 8
x² = 4/9
x = ± 2/3
x¹ = 2/3
x² = - 2/3
№123.
А) (а+8)•40=40а+320 Б) (12-b)•7=84-7b В) 12•(6+с)=72+12c Г) 10•(d-8)=10d-80
№124.
А) 1495•211+211•1505=211*(1495+1505)=211*3000=633000
Б) 3249•627-627•3049= 627*(3249-3049)=627*200=125400
В) 934•124-617•124+683•124=124*(934-617+683)=124*(934+683-617)=
=124*(1617-617)=124*1000=124000
№125.
А) 24a+16a=40a E) 12z-z=11z Ж)135n+286n-121n=300n
№126
А) 37m+63m=100m
если m=37 100*37=3700
если m=8 100*8=800
№127
А) 34x+17x=1173
51х=1173
х=1173:51
х=23
Б) 48y-25y=437
23у=437
у=437:23
у=19