SOLUTION: The difference of two numbers is 86. The second is 6 less than 5 times the first. What are the two numbers?

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Question 112043: The difference of two numbers is 86. The second is 6 less than 5 times the first. What are the two numbers?
Found 2 solutions by jim_thompson5910, BrittanyM:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=1st # and y=2nd #

Translate the following:

"The difference of two numbers is 86" becomes x-y=86

"The second is 6 less than 5 times the first" becomes y=5x-6

Start with the given system
x-y=86
y=5x-6



x-%285x-6%29=86 Plug in y=5x-6 into the first equation. In other words, replace each y with 5x-6. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


x-5x%2B6=86 Distribute the negative


-4x%2B6=86 Combine like terms on the left side


-4x=86-6Subtract 6 from both sides


-4x=80 Combine like terms on the right side


x=%2880%29%2F%28-4%29 Divide both sides by -4 to isolate x



x=-20 Divide




Now that we know that x=-20, we can plug this into y=5x-6 to find y



y=5%28-20%29-6 Substitute -20 for each x


y=-106 Simplify


So our answer is x=-20 and y=-106

Answer by BrittanyM(80) About Me  (Show Source):
You can put this solution on YOUR website!
With the information which we have been given, we can set up equations to solve for the variables.

The difference of the two numbers is 86:
-x + y = 86

The second is 6 less than 5 times the first:
y = 5x - 6

we can put these together as a system:
-x + y = 86
5x - y = 6

By using the elimination method, we have
4x = 92
x = 23

Now using the method of substitution, we can plug 23 into one of the equations to find y.

-(23) + y = 86
y = 109

We can check our answer by plugging both values in for x and y.

-(23) + (109) = 86
86 = 86

5(23) - (109) = 6
6 = 6

Both of these statements are true,
x = 23
y = 109