Question

Cara penyelesaian no8 ?

Answer 1

8. 
a + 2b = 18
a + 6b = 38
------------- -
    -4b = -20
       b = 5

a + 6b = 38
a + 6.5 = 38
a + 30 = 38
a = 38-30
a = 8

S24 = n/2 (2a+(n-1)b)
       = 24/2 (2.8 + (24-1).5)
       = 12 (16 + 23.5)
       = 12 . (16 + 115)
       = 12. 131
S24 = 1572