Jawapan

2016-10-18T20:25:49+08:00
(4r - 8a) + (r - a)
=4r + r - 8a - a
=5r - 9a
2016-10-18T20:27:12+08:00
(4r-8a)+(r-a)=

4r-8a+r-a=

4r+r-8a-a=

jawapan: 5r-9a