3x+7=-x-1
move -x to the other side
sign changes from -x to +x
3x+x+7=-x+x-1
3x+x+7=-1
4x+7=-1
move 7 to the other side
sign changes from +7 to -7
4x+7-7=-1-7
4x=-8
Divide by 4 for both sides
4x/4=-8/4
Answer: x=-2
20% off means you paid only 80% of the original price.
0.8x=40
x=40÷0.8=50
so the original price is 50
Answer:
z=-y-11
Step-by-step explanation:
let's take out the parenthesis
-z-11=y
Now put 11 on the other side
-z=y+11
Then make z positive
z=-y-11
3t-7=5t
-3t -3t
-7 = 2t
/2 /2
t = -7/2
Plug it in to 6t, so it is 6(-7/2) = -21