[tex]1a. \: \: 3a + 4a = 7a[/tex]
[tex]1b. \: \: 6ab + 3ab - ab \\ = 9ab - ab \\ = 8ab[/tex]
[tex]1c. \: \: 8u + 3y - 10u + 2y \\ = (8u - 10u) + (3y + 2y) \\ = - 2u + 5y[/tex]
[tex]2a. \: \: 8 {a}^{2} + 6 a + 10 \: dan \: 2 {a}^{2} + 4 {a} + 3 \\ = (8a^{2} + 2 {a}^{2} ) + (6a + 4a) + (10 + 3) \\ = 10 {a}^{2} + 10a+ 13[/tex]
[tex]2b. \: \: 3p + 2q - 3r \: dan \: 4p - 7r \\ = (3p + 4p) + (2q) - (3r - 7r) \\ = 7p + 2q - ( - 4r) \\ = 7p + 2q + 4r[/tex]
[tex]3a. \: \: 2a + 3b - 5ab + 6a - 10b \\ = (2a + 6a) + (3b - 10b) - 5ab \\ = 8a + ( - 7b) - 5ab \\ = 8a - 7b - 5ab[/tex]
[tex]3b. \: \: 4u - 3y + 5 + 10u - 7y - 12 \\ = (4u + 10u) - (3y - 7y) + (5 - 12) \\ = 14u - ( - 4y) + ( - 7) \\ = 14u + 4y - 7[/tex]
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