用代入法解下列方程組,不要直接給答案. (1)3x + 4y = 16① 5x - 6y = 33② (2)4(x-y-1)= 3(1-y)- 2① x/2 + y/3 =2②

用代入法解下列方程組,不要直接給答案. (1)3x + 4y = 16① 5x - 6y = 33② (2)4(x-y-1)= 3(1-y)- 2① x/2 + y/3 =2②

1
3x+4y=16兩邊都乘以3為9x+12y=48再進行一個移項12y=48-9x
5x-6y=33兩邊都乘以2為10x-12y=66
12y帶入第二個方程
10x-48+9x=66
19x=114
x=6
y=-1/2
2
4(x-y-1)= 3(1-y)- 2簡化後得y=4x-5
x/2 + y/3 =2兩邊都乘以6 3x+2y=12
將y帶入3x+2y=12
3x+8x-10=12
11x=22
x=2
y=3