Question

Jika 3m(am + 4) = 15m2 + bm, maka nilai ab(a + b) = ....
(Sumber : Kurniawan, 2013. Mandiri Matematika 1. Jakarta : Erlangga)
Select one:
a. 420
b. 1.020
c. 289
d. 1.200
pliss dijawabb

Answer 1

Jawabannya yang b.

3a = 15
  a = 5

  b = 3 x 4
  b = 12

ab (a + b) = 60 (5 + 12) = 60 (17) = b. 1.020

Answer 2

3m(am + 4) = 15m^2 + bm
3am^2 + 12m = 15m^2 + bm

3a = 15
a = 15/3
a = 5

12 = b

ab(a+b)
= 5.12(5 + 12)
= 60 (17)
= 1.020

jawaban B