Answer: I think 13
Step-by-step explanation:
Answer:
-1
Step-by-step explanation: from the equation, x-y=8, make y the subject of the formulae , this gives - y= -x +8
divide all through by (-) sign, this gives y= x - 8
from the last equation above, the slope is the coefficient of x which is 1. since it is perpendicula, the answer is -1
by co efficient, we mean the number multiplying the unknown
Answer: It was marked down by 35%
Step-by-step explanation:
1. find the difference of the two prices, 68-44.20=23.8
Take the fraction 23.8/68 (because that is how much the price changed and you need to find what percent that is.
You get 35%
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.
