SOLUTION: Please help me make this into an inaquality and solve as well. The difference of three times a number and 5 is more than the number times 4.

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Question 664869: Please help me make this into an inaquality and solve as well. The difference of three times a number and 5 is more than the number times 4.
Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website!
3x - 5 > 4x
x is the number
the difference of 3 times the number and 5 is equivalent to 3x - 5
more than the number times 4 is equivalent to > 4x + 5
the equation is 3x-5 > 4x
subtract 4x from both sides of the equaton to get 3x - 5 - 4x > 0
combine like terms to get -x - 5 > 0
add 5 to both sides of the equation to get -x > 5
multiply both sides of the equation by -1 to get x < -5
note that multiplying both sides of an inequality by a negative number reverses the inequality.
your solution should be x < -5
you need to substitute for x in your original equation to see if this solution is good.
your original equation is 3x - 5 > 4x.
pick a number for x < -5.
let's try -6.
your original equation is 3x - 5 > 4x
replace x with -6 to get 3(-6) - 5 > 4(-6)
simplify to get -18 - 5 > -24
combine like terms to get - 23 > -24 which is true.
this means your solution is good.
let's try a much larger difference to see it it's still true.
let's try x = -20
your original equation is 3x - 5 > 4x
replace x with -20 to get 3(-20) - 5 > 4(-20)
simplify to get -60 - 5 > -80
combine like terms to get -65 > -80
since -65 > -80 is a true statement, your solution is good.