Let the width be w, then length = 2w - 1
Area = length times width = w(2w - 1) = 21.
Thus, 2w^2 - w = 21 or 2w^2 - w - 21 = 0
Solving the quadratic equation gives that w = 3.5.
Therefore, width is 3.5 ft and length is 2(3.5) - 1 = 6 ft.
-5x + y = -5.....multiply by -2
-4x + 2y = 2
---------------
10x - 2y = 10 (result of multiplying by -2)
-4x + 2y = 2
-----------------add
6x = 12
x = 12/6
x = 2
-5x + y = -5
-5(2) + y = -5
-10 + y = -5
y = -5 + 10
y = 5
solution is (2,5)
Answer:
$14000
Step-by-step explanation:
Given parameters:
Amount earned by employee x = $5250
Time duration = 3weeks
Unknown:
Amount earned in 8 weeks = ?
Solution:
Let us first find the rate of employee x earning;
Rate = 
Insert parameters;
Rate = 
= $1750/week
So,
In 8 weeks;
Amount earned = rate x time duration
Amount earned = $1750/week x 8weeks
Amount earned = $14000
X + y = 20 --> eqn 1
The second equation would be the mass balance shown below:
(x)(0.40) + y(0.70) = 20(0.52) --> eqn 2
Rearranging eqn 1,x = 20 - ySubstitute this to eqn 2:
(20 - y)(0.40) + y(0.70) = 20(0.52)Solve for y,y = 8 grams Finally, solve for x.x = 20 - 8 = 12 grams
Therefore, Serena needs 12 grams of the 40% solution and 8 grams of the 70% solution.
