Answer:
the answer is
Step-by-step explanation:
D
Perimeter of a parallelogram = 2(a+b)
Perimeter of parallelogram mnpq = 68 inches
<span>mn is seven inches longer than twice the length of side np
let the length of np = x
length of mn= 2x + 7
Now,
p = 2(2x+7+x)
68 = 4x + 14 + 2x
68 = 6x + 14
6x = 68 - 14
6x = 54
x = 9
Thus, the length of np is 9 inches.
</span>
Answer:
80%
Step-by-step explanation:
There are 100 parts in a percent so 20-100 equals 80 so your answer is 80%
We want to see how much pure water and 80% salt solution should be mixed to get 20 ounces of a 50% salt solution, we will solve this by using a system of equations. We will see that we need to use <u>7.5 ounces of pure water</u> and <u>12.5 ounces of the 80% salt solution.</u>
<h3>
How to get the system of equations?</h3>
We should start by defining the variables we will be using, these are:
- x = ounces of pure water used
- y = ounces of the 80% solution used.
We know that we want to end with 20 ounces of the mixture, then we have:
x + y = 20
We also know that the percentage of salt in the final mixture must be 50%, which means that a 0.5 of the final mixture is salt, then we have:
0*x + 0.8*y = 0.5*20
(the first 0 is because we have no salt in the pure water, and the 0.8 is because we have 80% of salt in the 80% mixture)
So we got the two equations needed, thus the system of equations is:
x + y = 20
0*x + 0.8*y = 0.5*20
With the second one we can get the value of y:
0*x + 0.8*y = 0.5*20
0.8*y = 0.5*20 = 10
y = 10/0.8 = 12.5
This means that we must use 12.5 ounces of the 80% solution, and we need to use:
x = 20 - y = 20 - 12.5 = 7.5
7.5 ounces of pure water.
If you want to learn more about systems of equations, you can read:
brainly.com/question/13729904
Answer: The expression, 8 x 54, may also be expressed as 8 x 50 + 8 x 4 because by factoring the 8,
8 x (50 + 4) = 8 x 54
Further, it can also be expressed as,
8 x 60 - 8 x 6
because,
8 x (60 - 6) = 8 x 54
Step-by-step explanation:
