Answer: One plain roll is 4 dollars and one shiny roll is 6 dollars.
Step-by-step explanation:
lets start by saying
rolls of plain wrapping paper = x
rolls of shiny wrapping paper = y
Kathryn sold 4 plain rolls and 3 shiny rolls for 34 dollars.
4x+3y=34
Eugene sold 4 plain rolls and 2 shiny rolls for 28 dollars
4x+2y=28
Both equations will look like this.
4x+3y=34
-1(4x+2y)=(28)-1
we can multiply the second equation by -1 to get y alone. (doesn't matter which equation). Once you do that, the positive 4x and the negative 4x cancel out, 3y-2y=1y and 34-28=6. you are left with
1y=6 so one shiny roll is 6 dollars.
now use that price to find the cost of the plain roll.
lets use Kathryn's equation
4x + 3(6)=34
4x + 18= 34
-18 -18
4x=16. Divide by 4 to find cost of one plain roll.
16÷4=4. One plain roll costs 4 dollars.
Lets check. Using Kathryn's equation,
4(4) + 3(6)=34
16+18=34
34=34. We are right.
Answer:
y= 2/3x -1
Step-by-step explanation:
Ok so basically we want to put it in the form y=mx+b where m is 2/3 and passes through the point (9,5). So sub in the x and y of the point in brackets into the equation. 5= 2/3(9) + b and solve for b so b = -1. Therefore the equation is y=2/3x -1
When
, you have
Now assume this is true for
, i.e.
and under this hypothesis show that it's also true for
. You have
In other words, there exists
such that
Rewriting, you have
and this is equivalent to
modulo 9, as desired.
Answer:
D because we just distribute the 0.5
Hope this helps and brainliest please
