Answer: S=20
Explanation:
Data: 3=-2(0.25s-5)+3
S=?
Step one, Multiply .25s and -5 by -2
-2x0.25s=-0.50s
-2x-5=10
Reason: When something is in parenthesis, that is the first thing you evaluate, and since -2 is right next to the parenthesis, you multiply both numbers by -2 to get -.50s and 10
Step two, add like terms
3=-.50s+10+3=3=-.50s+13
Reason: When there are like terms(terms with the same variable or same exponent, etc.) You have to add them or else evaluating things will get harder to do as you go on, in this case, the two like terms(3 and 10) added together get 13.
Step three, subtract 13 on both sides
3-13=-.50s+13-13
-10=-.50s
Reason: Because the point of this is to single out 's', you have to get rid of the 13 and since it's a positive 13, you add it to a negative to cancel it out, but what you do to one side you do to the other so you subtract 13 from 3 to get negative 10.
Step four, divide -.50 on both sides
-10/-.50=-.50s/-.50
S=20
Reason: Since you have to isolate 's' and it's right next to -.50(which means multiplication), you have to divide it to get rid of it. Since what you do to one side you do to the other, you divide -10 by -.50 to get 20=S
That's how you get the answer
I hope this helps!