Question

Jika -x+3y=7
4x+3y=17
ax+by=7 dan ax=by=1
maka a-b=

Answer 1

-x + 3y = 7
4x + 3y = 17
------------------ -(dikurang)
-5x = -10
x = -10/-5 = 2

-x + 3y = 7
(-2) + 3y = 7
3y = 7 + 2
3y = 9
y = 9/3 = 3

ax + by = 7
ax = by = 1
2a = 3b = 1
**** 2a = 1
a = ½
***** 3b = 1
b = ⅓

Jadi, a – b = ½ – ⅓
= 3/6 – 2/6 = 1/6