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​Julio says, If you subtract 18 from my number and multiply the difference by -5 ​, the result is-80 ​. What is ​s ​number?

User Vinceh
by
5.5k points

2 Answers

5 votes

Answer:


s=34

Explanation:

Set up an equation using the given information:

  • our number is represented by s
  • subtract 18 from s
  • multiply the difference by -5
  • result is -80

"Multiply the difference" suggests that the subtraction should be done first. Following PEMDAS, in order to get subtraction done first, it would need to be in parentheses:


(s-18)

Then you would multiply that difference by -5:


-5*(s-18)

Now set the expression as equal to -80:


-80=-5(s-18)

Now you can solve for s. Use the distributive property:


-80=-5(s)-5(-18)\\\\-80=-5s+90

Isolate the variable s. Subtract 90 from both sides:


-80-90=-5s+90-90\\\\-170=-5s

Divide both sides by -5:


(-170)/(-5)=(-5s)/(-5) \\\\34=s

Your number is 34.

:Done

Check answer:

Insert the value of s into the equation to determine if true:


-80=-5(34-18)\\\\-80=-5(16)\\\\-80=-80

This is true, so the value of s is correct.

User Adrian World
by
5.9k points
4 votes

Answer:

34 is your answer

Explanation:

34-18=16

16(-5)=-80

User Dmitry  Skryabin
by
6.6k points