Elimination:
7x - 3y = 20
5x + 3y = 16
(add)
12x = 36
÷ 12
x = 3
(5 × 3) + 3y = 16
15 + 3y = 16
- 15
3y = 1
÷ 3
y = 1/3
Substitution:
5x + 3y = 16
- 3y
5x = 16 - 3y
÷ 5
x = 3.2 - 0.6y
5(3.2 - 0.6y) + 3y = 16
16 - 3y + 3y = 16
16 = 16
- 16
6y = 0
÷ 6
y = 0
Sorry the substitution messed up for some reason, I'll fix it after I've answered the other question
Are you able to ask your teacher?
Well, first fin dyour best estimate mine is...600
Then after you got your best estimate divide that my 20
600/20 = 30
Hope this helped :D
Answer: There is no picture!!??
Step-by-step explanation:
Answer:
1. {5,-9}
2.{4}
3.{9/2}
Step-by-step explanation:
The equation
can be solved as follows:




Then, the solutions of the equation are
.
Now, if
, we can solve the equation
as follows:




So, the unique solution of this last equation is 
The last equation is
, where
. To solve this equation we can proceed as follows:







But, x=11/4 is not a solution of this equation. So the unique solution is x=9/2.