SOLUTION: Not sure how to solve this problem on my daughters homework. I would like to understand so I can attempt to explain it to her. Here it is.. The difference of two numbers is 8. The

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Not sure how to solve this problem on my daughters homework. I would like to understand so I can attempt to explain it to her. Here it is.. The difference of two numbers is 8. The       Log On


   



Question 512072: Not sure how to solve this problem on my daughters homework. I would like to understand so I can attempt to explain it to her. Here it is.. The difference of two numbers is 8. The first number x is 1 less than twice the second number y. Write and solve a system of linear equations to find the two numbers
Found 2 solutions by scott8148, stanbon:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
"The first number x is 1 less than twice the second number y" ___ x = 2y -1

"The difference of two numbers is 8" ___ x - y = 8

substituting the equivalent value for x from the 1st equation ___ (2y - 1) - y = 8
___ y = 9

substituting into the 2nd equation ___ x - (9) = 8
___ x = 17

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The difference of two numbers is 8. The first number x is 1 less than twice the second number y. Write and solve a system of linear equations to find the two numbers
-----
Equations:
x - y = 8
x = 2y -1
----
Substitute the expression for "x" into the 1st equation.
Then solve for "y":
(2y-1) - y = 8
2y-y-1 = 8
y - 1 = 8
y = 9
-----------------
Now, solve for "x":
x = 2y-1
x = 2*9-1
x = 18-1 = 17
==================
Solution: x = 17 ; y = 9
=============================
Cheers,
Stan H.
==============