Given:
The system of equations is
![y=2x-5](https://tex.z-dn.net/?f=y%3D2x-5)
![2y-4x=?](https://tex.z-dn.net/?f=2y-4x%3D%3F)
To find:
The missing value for which the given system of equations have infinitely many solutions.
Solution:
Let the missing value be k.
We have,
![y=2x-5](https://tex.z-dn.net/?f=y%3D2x-5)
![2y-4x=k](https://tex.z-dn.net/?f=2y-4x%3Dk)
Taking all the terms on the left side, the given equations can be rewritten as
![-2x+y+5=0](https://tex.z-dn.net/?f=-2x%2By%2B5%3D0)
![-4x+2y-k=0](https://tex.z-dn.net/?f=-4x%2B2y-k%3D0)
The system of equations
and
have infinitely many solutions if
![\dfrac{a_1}{a_2}=\dfrac{b_1}{b_2}=\dfrac{c_1}{c_2}](https://tex.z-dn.net/?f=%5Cdfrac%7Ba_1%7D%7Ba_2%7D%3D%5Cdfrac%7Bb_1%7D%7Bb_2%7D%3D%5Cdfrac%7Bc_1%7D%7Bc_2%7D)
We have,
![a_1=-2,b_1=1,c_1=5](https://tex.z-dn.net/?f=a_1%3D-2%2Cb_1%3D1%2Cc_1%3D5)
![a_2=-4,b_2=2,c_2=-k](https://tex.z-dn.net/?f=a_2%3D-4%2Cb_2%3D2%2Cc_2%3D-k)
Now,
![\dfrac{-2}{-4}=\dfrac{1}{2}=\dfrac{5}{-k}](https://tex.z-dn.net/?f=%5Cdfrac%7B-2%7D%7B-4%7D%3D%5Cdfrac%7B1%7D%7B2%7D%3D%5Cdfrac%7B5%7D%7B-k%7D)
![\dfrac{1}{2}=\dfrac{1}{2}=\dfrac{5}{-k}](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B2%7D%3D%5Cdfrac%7B1%7D%7B2%7D%3D%5Cdfrac%7B5%7D%7B-k%7D)
![\dfrac{1}{2}=\dfrac{5}{-k}](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B2%7D%3D%5Cdfrac%7B5%7D%7B-k%7D)
On cross multiplication, we get
![-k=10](https://tex.z-dn.net/?f=-k%3D10)
![k=-10](https://tex.z-dn.net/?f=k%3D-10)
Therefore, the missing value is -10.
Answer:
SA = 1099 square inches.
Step-by-step explanation:
Just plug into the formula
SA = 2pir^2 + 2pi r h where pi = 3.14, r = 5 and h = 30
SA = 2 (3.14) (5^2) + 2 (3.14)(5)(30)
SA = 157 + 942
SA = 1099 square inches.
Answer:
740 m^2
Step-by-step explanation: