Answer:
7.
Step-by-step explanation:
9y+12=75
subtract 12 from 75
divide by 9y
BD=7x-10
Answer: x=bd/7 + 10/7
BC=4x-29
Answer: x=Bc/4 + 29/4
CD=5x - 9
Answer: x= cd/5 + 9/5
In order to use substitution, you need to isolate a variable on one of the equations:
-2x+y=0
y=2x
Then you plug that equation into the other equation. Since we isolated y, we plug in 2x for y in the other equation:
3x-(2x)=5
x=5
Then plug the value you found into any equation to solve for the other variable:
3(5)-y=5
15-y=5
-y=-10
y=10
So your answers are x=5, y=10
You can assume that my answer is correct because I have done the assignment before the answer is 20m
