SOLUTION: five times the opposite of a number was increased by 25. This was exactly 90 greater than 8 times the number. What was the number?

Algebra ->  Equations -> SOLUTION: five times the opposite of a number was increased by 25. This was exactly 90 greater than 8 times the number. What was the number?      Log On


   

Question 15973: five times the opposite of a number was increased by 25. This was exactly 90 greater than 8 times the number. What was the number?
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
five times the opposite of a number was increased by 25. This was exactly 90 greater than 8 times the number. What was the number?
let x = the number
-x = the opposite of the number
So we have 5 times(*) the opposite;
5(-x)=-5x
was increased(+) by 25;
-5x+25
This was exactly(=)
90 greater than(+)
8 times the number=8x
So lets put it all together;
-5x+25=8x+90
And there is our equation, now lets solve;
Subtract 90 from both sides and add 5x;
-5x+25+5x-90=8x+90+5x-90
25-90=8x+5x
-65=13x
Divide each side by 13;
-65%2F13=13x%2F13
-5=x
Hope you understand
=)