Jawabanmu

2014-08-27T16:24:16+07:00
A. 12+2(4x-3)
     = 12+8x-6
     = 6+8x
B. 8(3x+4y) - 5(4x-6y)
    = (24x+32y) - (20x-30y)
    = 24x-20x+32y+30y
    = 4x+62y
C. a(a+3b) + 2a(4a+5b)
    = a^{2} +3ab+8 a^{2} +10ab
    =9 a^{2} +13ab
D. 5x(4x-3y) - 3x(5x+2y)
    = 20 x^{2} -15xy-15 x^{2} -6xy
    = 35 x^{2} -21xy
2014-08-27T16:47:06+07:00
A. 12+2(4x-3) = 12 + 8x - 6 = 6 + 8x disederhanakan (dibagi 2) manjadi
               4x + 3

B. 8(3x+4y) - 5(4x-6y) = 24x + 32y - 20x + 30y
              = 4x + 62y = 2x + 31y

C. a(a+3b) + 2a(4a + 5b) = a² + 3ab + 8a² + 10ab
              = 9a² + 13ab

D. 5x(4x-3y) - 3x(5x+2y) = 20x² - 15xy - 15x² - 6xy
            = 5x² - 21xy

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