SOLUTION: my math teacher is literally horrible at teaching and every year 75% of his class fails and i am in that position as of now. i have never been good at math but i catch on if explai

Algebra ->  Systems-of-equations -> SOLUTION: my math teacher is literally horrible at teaching and every year 75% of his class fails and i am in that position as of now. i have never been good at math but i catch on if explai      Log On


   

Question 27243: my math teacher is literally horrible at teaching and every year 75% of his class fails and i am in that position as of now. i have never been good at math but i catch on if explained clearly but he does not take the time to do that so i am stuck. please help me figure this out!
Solve the system of equations:
y=3x
2x+y=5
i have asked my family but they really have no idea how to do it either. i have tried to figure it out but i keep getting the same wrong answer.
my steps:
y=3x
2x+y=5
3x+2x= 5x
5x/5= 1
3x(1)= 3
x=3
y=3x=3 x 3= 9
y=9
but that answer is incorrect :( so if you could please help me to figure out what im doing wrong and explain to me the steps it would be greatly appreciated! thank you
failing algebra,
whitney







Answer by rodriguezh2(15) About Me  (Show Source):
You can put this solution on YOUR website!
Whitney
you have two equations:
y = 3x
2x + y = 5
We know what y is right? It is 3x. So we can plug in 3x for y:
2x + (3x) = 5 Now we add 2x + 3x
5x = 5 Now we divide both sides by 5
x = 1
Now we plug x into y = 3x to solve for y
y = 3(1)
y = 3
So x = 1 and y = 3
Hope this helped :)
Remember whenever you have two variables (x and y) you need two equations to solve for it