Question 124242: Solve by substitution or elimination:
x=3y+11
2x+5y=0
I dont understand could I please have help for this question?
Found 2 solutions by Fombitz, solver91311:
Answer by Fombitz(32388)   (Show Source):
Answer by solver91311(24713)  (Show Source):
You can put this solution on YOUR website! 
Substitution:
The first equation is already solved for x, so you can take the right-hand expression and substitute it for x into the second equation:
Simplify and solve:
Now that you have a value for y, you can substitute that back into either equation to solve for x:
So the solution set for this system is the ordered pair (5,-2)
Elimination:
Your second equation is in standard form ( ), so put the first equation into standard form as well.
1.
2.
The idea is to multiply one or both of the equations by a constant or constants so that the coefficients on one of the variables will become additive inverses. In this case, multiplying the first equation by -2 will give you a -2x in the first equation and 2x in the second equation.
3. 
2.
Now add the two equations, term by term:
4. 
And solve:
Now you can do either of two things. One, you can substitute this value for y back into either of the original equations and solve for x. Or two, you can go back to the original equations, find a different multiplier or multipliers that will allow you to eliminate the y variable and solve for x.
We've already done the first way as the second step of the substitution method, so let's try the second way:
1.
2.
Multiply the first equation by 5 and the second equation by 3
3. 
4. 
Add the equations, term-by-term:
5. 
Solve
And again, the solution set is the ordered pair (5,-2). I sincerely hope that you weren't surprised that we got the same answer with either method.
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