1.(3a+a)(a+b) 2.5(x-y+2) 3.3(2x+y)+2(2x-y) 4.(-a+2)(a+3) 5.(2x+3)²

1. (3a + a)(a+b) = 4a(a + b) = 4axa + 4axb = 4a^2 + 4ab
2. 5(x - y + 2) = 5*x - 5*y + 5*2 = 5x - 5y + 10
3. 3(2x + y) + 2(2x - y) = 3*2x + 3*y + 2*2x - 2*y = 6x + 3y + 4x - 2y = 10x + y
4. (-a + 2)(a + 3) = -axa + -ax3 + 2xa + 2x3 = -(a^2) + -3a + 2a + 6 = -(a^2) - a + 6
5. (2x + 3)^2 = (2x + 3)*(2x + 3) = 2x*2x + 2x*3 + 3*2x + 3*3 = 4(x^2) + 6x + 6x + 9
                      = 4(x^2) + 12x + 9

Tanda * untuk menggantikan kali (x) saat soal memakai variabel x, biar tidak bingung