SOLUTION: Use substitution to solve each system of equations. If the system does not have exactly one solution, state whether it has no solution or infinitely many solutions. x-3y=0

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Question 80293This question is from textbook Algebra I
: Use substitution to solve each system of equations. If the system does not have exactly one solution, state whether it has no solution or infinitely many solutions.
x-3y=0
3x+y=7 This question is from textbook Algebra I

Answer by sofiyacherni(99) About Me  (Show Source):
You can put this solution on YOUR website!
from first equation you want to move 3y to the other side so technically you want to add 3y to both sides so that 3y on the left of equal signs becomes zero
x-3y%2B3y=0%2B3y so *** x=3y
now that you have a formula for x you have to substitute it in the second equation
3%283y%29%2By=7
9y%2By=7 so 9y+1y=10y, then
10y=7 in order for you to get y by itself you have to divide both sides by 10, thus
%2810y%29%2F10=7%2F10 two tens on the left cancel out and you are left with
y=7%2F10
now that you have a value for y go back to equation marked *** and substitute 7%2F10 for y to find the value for x, you get
x=3%287%2F10%29=21%2F10
thus your answer is x=21%2F10 and y=7%2F10
Good Luck