Answer
Price she bought it is 3 - 0.75 = 2.25
Percent dicount = (0.75/3) * 100 = 25%
Step-by-step explanation:
Answer:

Step-by-step explanation:
Since you multiply 3 by itself 3 times, that becomes
and since you multiply 4 by itself 3 times, that becomes
.
The final product is
.
Equations:
4x - 2y = 12
-4x - 9y = 54
Multiple them in both sides
4x - 2y - 4x - 9y = 12 + 54
-2y - 9y = 66
-11y = 66
y= -6
If y= -6 then put y in first or second equation.
I put it in first equation
4x - 2.(-6) = 12
4x + 12 = 12
x= 0
Therefore
(x,y) = (0, -6)
X=width of a coccer pitch
2x-20=length of a soccer pitch
Area (rectangule)=length x width
We suggest this equation:
x(2x-20)=6000
2x²-20x=6000
2x²-20x-6000=0
x²-10x-3000=0
We solve this quadratic equation:
x=[10⁺₋√(100-4*1*-3000)]/2=[10⁺₋√(100+12000)]/2=
=(10⁺₋110)/2
we have two solutions:
x₁=(10-110)/2=-50, invalid solution.
x₂=(10+110)/2=60
x=60
2x-20=2(60)-20=120-20=100
Solution: the length is 100 m, and the width is 60 m.
To check:
Area=100 m*60 m=6000 m²
The twice of width is =2(60 m)=120 m,
20 m less than twice its width is: 120 m-20 m=100 m=the length.
45 + 4 makes 49 if that counts