JAMB - Mathematics (1984 - No. 19)
If 2x + 3y = 1 and x - 2y = 11, find (x + y)
5
-3
8
2
-2
Açıklama
2x + 3y = 1 x 2.......(i)
x - 2y = 11 x 3.......(ii)
4x + 6y = 2........(iii)
3x - 6Y = 33........(4)
7x = 35
x = 5
Subt. for x
10 + 3y = 1
3y = -9
y = -3
x + y = 5 + -3
5 - 3 = 2
x - 2y = 11 x 3.......(ii)
4x + 6y = 2........(iii)
3x - 6Y = 33........(4)
7x = 35
x = 5
Subt. for x
10 + 3y = 1
3y = -9
y = -3
x + y = 5 + -3
5 - 3 = 2