SOLUTION: solve and check: 1. 5.6(s+7)=34.4+6.8s multiply 2. (x^2-7x+5)(3x-3) factor 3.21c^2+6cy-35c-10y

Algebra ->  Expressions -> SOLUTION: solve and check: 1. 5.6(s+7)=34.4+6.8s multiply 2. (x^2-7x+5)(3x-3) factor 3.21c^2+6cy-35c-10y       Log On


   



Question 174254: solve and check:
1. 5.6(s+7)=34.4+6.8s
multiply
2. (x^2-7x+5)(3x-3)
factor
3.21c^2+6cy-35c-10y

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
1. 5.6(s+7) = 34.4 + 6.8s
Multiply equation by 10 to get rid of those annoying decimals
56(s+7) = 344 + 68s
:
56s + 392 = 344 + 68s
:
392 - 344 = 68s - 56s
:
48 = 12s
s = 48%2F12
s = 4
:
Check solution in original equation:
5.6(4+7) = 34.4 + 6.8(4)
5.6(11) = 34.4 + 27.2
61.6 = 61.6; confirms our solution of s=4
:
:
multiply
2. (x^2-7x+5)(3x-3)
Multiply it like you learned to do to numbers in the 3rd grade
x^2 - 7x + 5
.......*..3x - 3
-------------
You should get: 3x^3 - 24x^2 + 36x - 15
;
;
factor
3. 21c^2 + 6cy - 35c - 10y
Factor by groups
3c(7c + 2y) - 5(7c + 2y)
factor out (7c+2y) and you have:
(7c+2y)(3c - 5)
:
Any questions about this stuff?