how do you solve multi-step equations?

Question

I need help with these.2(2.5b -9) +6b =7, and12y = 2y +40, and 6(c +4) = 4c -18. thanks .

Answer 1

2(2.5b -9) +6b =7 disribute 2
5b-18+6b=7 add 18
11b=25 divide 11
b=25/11=2 3/11=2.727

12y = 2y +40 subtract 2y
10y=40 divide by 10
y=4

6(c +4) = 4c -18 distribute 6
6c+24+4c-18 subtract 4c+24
2c=-42 divide by 2
c=-21

Answer 2

1) 2(2.5b-9)+6b=7
a.distributive property(5b-18)+6b=7
b.Combin like terms. 11b-18=7
c.Get 11b by itself. Add 18 to both sides of the equation. 11b=25
d.Divide both sides by 11.
e.The answer is either 25/11 or 2.27(repeating.

2)answer y=4
3)answer c= -21

Answer 3

(1) 2(2.5b-9)+6b=7
i.e.5b-18+6b=7
i.e.5b+6b=7+18
i.e.11b=25
i.e. b=25/11=2 3/11

(2) 12y=2y+40
i.e.12y-2y=40
i.e. 10y=40
i.e. y= 4

(3) 6(c+4)=4c-18
i.e.6c+24=4c-18
i.e.6c-4c= -18-24
i.e.2c= -42
i.e.c= -21

Answer 4

First get rid of the parenthesis, do the distributive property. Then combine like terms. Then undo the constant (number without a variable). Last undo the coefficient (number with the variable).

Answer 5

2(2.5b-9)+6b=7
5b-18+6b=7
11b-18=7
+18=+18
---------------------
11b=25
----- -----
11 11
---------------
b= 25/11



12y=2y+40
-2y -2y
----------------
10y=40
-----------
10
--------------
y=4


6(c+4)=4c-18
6c+24=4c-18
-4c -4c
------------------------
2c+24=-18
-24 -24
------------------
2c=-42
----------
2
------------------------
c=-21