How many solutions does the following system have:
4x + 8y = 16
3x + 6y = 9
Explain how to determine the number of solutions without solving the system. Then apply elimination, and interpret the resulting expression

Question

How many solutions does the following system have: 
4x + 8y = 16 
3x + 6y = 9 
Explain how to determine the number of solutions without solving the system. Then apply elimination, and interpret the resulting expression

precal · Answer

the number of solutions is determined by the number of times these 2 lines cross

precal · Answer

if the slopes are the same, then the lines do not cross and therefore we say it has "no solution"
if the lines cross, then the cross point is the solution
if the lines are the same, they overlap each other and we say it has many solutions

precal · Answer

I can tell right away they are not the same

precal · Answer

2x+y=5
6x+3y=15
are the same do you see why?

precal · Answer

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