Solve the following equations:
1.22 - 3x = -8x - 8
2.-4分之-25 = -2x分之5
3.When x = -5, y = 2 and z = -1, find the values of the following:
a) (3x + 2y)(3z)
b) 2分之xy + 4分之yz + 5分之xz
關於數學問題 [20點!]
2010-08-09 10:16 pm
回答 (1)
2010-08-09 10:26 pm
✔ 最佳答案
1. 22-3x = -8x-85x = -30
x = -6
2. -25/-4 = 5/-2x
50x = -20
x = -2/5
3.a. (3x+2y)(3z)
= [3(-5) + 2(2)][3(-1)]
= [-15 + 6](-3)
= (-9)(-3)
= 27
b. xy/2 + yz/4 + xz/5
= (-5)(2)/2 + (2)(-1)/4 + (-5)(-1)/5
= -5 - 1/2 + 1
= -9/2
參考: Knowledge is power.
收錄日期: 2021-04-25 17:02:40
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100809000051KK00793