I know i got my answer wrong.
whatd you get?
can you help 15a + 12 = 3(3a – 7)?
2010-03-19 8:36 am
回答 (8)
2010-03-19 10:14 am
✔ 最佳答案
15a + 12 = 3(3a - 7)15a + 12 = 3(3a) - 3(7)
15a + 12 = 9a - 21
15a - 9a + 12 = -21
6a = -12 - 21
a = -33/6
a = -11/2 (-5.5)
2010-03-19 3:45 pm
First get rid of the parenthesis: 15a + 12 = 9a -21
then move variables to one side of the equation and numbers to the other side:
15a - 9a = -21 - 12
add or substract: 6a = -33
divide: a = -33/6
a = -5.5
then move variables to one side of the equation and numbers to the other side:
15a - 9a = -21 - 12
add or substract: 6a = -33
divide: a = -33/6
a = -5.5
2010-03-19 3:43 pm
a= -5.5 <--negative five point five
2010-03-19 3:42 pm
15a + 12 = 3(3a – 7)
15a + 12 = 9a - 21
15a + 12 - 12= 9a - 21 - 12
15a = 9a - 33
15a - 9a = 9a - 9a - 33
6a = -33
a = 5.5
15a + 12 = 9a - 21
15a + 12 - 12= 9a - 21 - 12
15a = 9a - 33
15a - 9a = 9a - 9a - 33
6a = -33
a = 5.5
2010-03-19 3:40 pm
15a + 12 = 3(3a – 7)
15a +12 -12 = 9a -21 -12
15a -9a = -33
6a = -33
a = -5 1/2
15a +12 -12 = 9a -21 -12
15a -9a = -33
6a = -33
a = -5 1/2
2010-03-19 3:39 pm
15a + 12 = 9a - 21
6a = - 33
2a = - 11
a = - 11/2
6a = - 33
2a = - 11
a = - 11/2
2010-03-19 3:39 pm
15a + 12 = 9a - 21
15a - 9a = -21 -12
6a = -33
a = -5.5
15a - 9a = -21 -12
6a = -33
a = -5.5
2010-03-19 3:39 pm
15a + 12 = 3(3a – 7)
15a+12=9a-21
15a-9a=-21-12
6a=-33
a=-33/6
a=-11/2
a=-5.5
Edit: sorry i missed the negative sign
15a+12=9a-21
15a-9a=-21-12
6a=-33
a=-33/6
a=-11/2
a=-5.5
Edit: sorry i missed the negative sign
收錄日期: 2021-05-01 13:03:13
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