Question

I NEED HELP.HOW DO I SOLVE THIS SOLVING BY SUBSTITUCION 5X+3Y=0
X-3Y=-18

Answer 1

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Answer 2

substitution method = substitute...
from your second eq: x=3y-18
substitute value of x in first eq:
5*(3y-18)+3y=0

solve it for y, then find x...
let me know if there is a problem :)

Answer 3

solve the second equation for x since it has a 1x as the number in front of the variable: x = 3y -18

plug the (3y - 18) in place of x in the first equation. (MAJOR RULE: You must always substitute into the other equation!!):
5(3y-18) +3y = 0
distribute:
15y - 90 + 3y =0
combine like terms and solve:
18y = 90
y = 5
Then plug in 5 for y in EITHER of the original equations. Choose the easier one: x - 3(5) =-18
then solve for x:
x - 15 = -18
x = -3

Final answer: (-3, 5)
you can check by plugging x and y into both equations to verify that it works for both. if it does, it has to be the right answer.