Multiply both siase of equation by 3
2x*3/3=4*3
2x=12
devide by 2
2x:2=12:2
x=6
Answer: x=6
Answer:
1/7
Step-by-step explanation:
Given that:
Using a scale factor of 7 ; the dimension of a rectangle is : 2 inches by 3 inches
In other to obtain the original size of the rectangle, all that is needed is to multiply the sacl d dimension by the reciprocal of the initi. Scale factor used, that is 1 / 7
This gives :
(2 inches by 3 inches) * 1/7
2/7 inches by 3/7 inches
Hence, required scale factor is 1/ 7
For this case we must indicate which of the equations shown can be solved using the quadratic formula.
By definition, the quadratic formula is applied to equations of the second degree, of the form:
![ax ^ 2+ bx+ c = 0](https://tex.z-dn.net/?f=ax%20%5E%202%2B%20bx%2B%20c%20%3D%200)
Option A:
![2x ^ 2-3x +10 = 2x + 21](https://tex.z-dn.net/?f=2x%20%5E%202-3x%20%2B10%20%3D%202x%20%2B%2021)
Rewriting we have:
![2x ^ 2-3x-2x+ 10-21 = 0\\2x ^ 2-5x-11 = 0](https://tex.z-dn.net/?f=2x%20%5E%202-3x-2x%2B%2010-21%20%3D%200%5C%5C2x%20%5E%202-5x-11%20%3D%200)
This equation can be solved using the quadratic formula
Option B:
![2x ^ 2-6x-7 = 2x ^ 2](https://tex.z-dn.net/?f=2x%20%5E%202-6x-7%20%3D%202x%20%5E%202)
Rewriting we have:
![2x ^ 2-2x ^ 2-6x-7 = 0\\-6x-7 = 0](https://tex.z-dn.net/?f=2x%20%5E%202-2x%20%5E%202-6x-7%20%3D%200%5C%5C-6x-7%20%3D%200)
It can not be solved with the quadratic formula.
Option C:
![5x ^ 2 + 2x-4 = 2x ^ 2](https://tex.z-dn.net/?f=5x%20%5E%202%20%2B%202x-4%20%3D%202x%20%5E%202)
Rewriting we have:
![5x ^ 2-2x ^ 2 + 2x-4 = 0\\3x ^ 2 + 2x-4 = 0](https://tex.z-dn.net/?f=5x%20%5E%202-2x%20%5E%202%20%2B%202x-4%20%3D%200%5C%5C3x%20%5E%202%20%2B%202x-4%20%3D%200)
This equation can be solved using the quadratic formula
Option D:
![5x ^ 3-3x + 10 = 2x ^ 2](https://tex.z-dn.net/?f=5x%20%5E%203-3x%20%2B%2010%20%3D%202x%20%5E%202)
Rewriting we have:
![5x ^ 3-2x ^ 2-3x + 10 = 0](https://tex.z-dn.net/?f=5x%20%5E%203-2x%20%5E%202-3x%20%2B%2010%20%3D%200)
It can not be solved with the quadratic formula.
Answer:
A and C