3s-4(1+3s)=8+3s
i got a different answer than my teacher and i was
wondering which was right. s= -1 or s= -2.
How often are teachers right?
3s - 4(1 + 3s) = 8 + 3s
3s - 4 - 12s = 8 + 3s
3s - 4 - 12s - 3s = 8 + 3s - 3s
-4 - 12s = 8
-4 - 12s + 4 = 8 + 4
-12s = 12
-12s / -12 = 12 / -12
s = -1
Check it by plugging the value for s into the equation.
3s - 4(1 + 3s) = 8 + 3s
3(-1) - 4(1 + 3(-1)) = 8 + 3(-1)
-3 - 4(1 - 3) = 8 - 3
-3 - 4(-2) = 5
-3 + 8 = 5
5 = 5
s = -1
Looks like this time your teacher was right.