SOLUTION: 2x+3y=24 y+7x=46 Im stuck from the very begining...

Algebra ->  Systems-of-equations -> SOLUTION: 2x+3y=24 y+7x=46 Im stuck from the very begining...      Log On


   



Question 141086: 2x+3y=24
y+7x=46
Im stuck from the very begining...

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Do you want to use substitution to solve this?


Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.


y%2B7x=46 Start with the second equation (Either equation will work, but y is easier to isolate in this equation)


y=46-7x Subtract 7x from both sides


y=-7x%2B46 Rearrange the equation

---------------------

Since y=-7x%2B46, we can now replace each y in the first equation with -7x%2B46 to solve for x



2x%2B3highlight%28%28-7x%2B46%29%29=24 Plug in y=-7x%2B46 into the first equation. In other words, replace each y with -7x%2B46. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.



2x%2B%283%29%28-7%29x%2B%283%29%2846%29=24 Distribute 3 to -7x%2B46


2x-21x%2B138=24 Multiply


-19x%2B138=24 Combine like terms on the left side


-19x=24-138Subtract 138 from both sides


-19x=-114 Combine like terms on the right side


x=%28-114%29%2F%28-19%29 Divide both sides by -19 to isolate x



x=6 Divide





-----------------First Answer------------------------------


So the first part of our answer is: x=6









Since we know that x=6 we can plug it into the equation y=-7x%2B46 (remember we previously solved for y in the first equation).



y=-7x%2B46 Start with the equation where y was previously isolated.


y=-7%286%29%2B46 Plug in x=6


y=-42%2B46 Multiply


y=4 Combine like terms



-----------------Second Answer------------------------------


So the second part of our answer is: y=4









-----------------Summary------------------------------

So our answers are:

x=6 and y=4

which form the point








Now let's graph the two equations (if you need help with graphing, check out this solver)


From the graph, we can see that the two equations intersect at . This visually verifies our answer.




graph of 7x%2By=46 (red) and 2x%2B3y=24 (green) and the intersection of the lines (blue circle).