SOLUTION: I need to solve the following word problem, I have to show the equation I use for the solution. One number is 7 less than another. If 4 times the smaller number plus 2 times t

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: I need to solve the following word problem, I have to show the equation I use for the solution. One number is 7 less than another. If 4 times the smaller number plus 2 times t      Log On


   



Question 185238: I need to solve the following word problem, I have to show the equation I use for the solution.

One number is 7 less than another. If 4 times the smaller number plus 2 times the larger number is 62, find the two numbers.
I just don't get these at all. Thanks, Dawn

Found 2 solutions by solver91311, josmiceli:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!

x is the large number

x - 7 is the smaller number

Four times the smaller number: 4(x - 7).

Two times the larger number: 2x.

So:



Solve for x to get one of the numbers, and then subtract 7 to get the other one.


John


Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let a= the larger number
Let b= the smaller number
given:
(1) b+=+a+-+7
(2) 4b+%2B+2a+=+62
-----------------
You have 2 equations and 2 unknowns. In all
cases where the number of unknowns = the number of equations,
the problem is solvable.
I'll substitute (1) in (2)
(2) 4%2A%28a+-+7%29+%2B+2a+=+62
(2) 4a+-+28+%2B+2a+=+62
(2) 6a+=+90
(2) a+=+15
Now plug this result back into (1)
(1) b+=+15+-+7
(1) b+=+8
The larger number is 15 and the smaller is 8
check answer:
(2) 4b+%2B+2a+=+62
(2) 4%2A8+%2B+2%2A15+=+62
(2) 32+%2B+30+=+62
(2) 62+=+62
OK