F(x) = 20x+300
you sub in the x values (120 hours and 100 hours) for each equation
the only one they both work for is the last one
f(x) = 20x + 300
f(100) = (20 * 100) + 300 = 2000 + 300 = 2300
f(120) = (20 * 120) + 300 = 2400 + 300 = 2700
Answer:
60
Step-by-step explanation:
A significant figure means the most important (biggest) number.
As it just wants 1 significant figure, you count 1 to the right and round the 6 up.
Hope this helps :)
Let the three apartments be A, B & C
The rent of A is $x
The rent of B is $y
The rent of C is $z
So x + y + z = 1600 .......(1)
Now
Maintenance of A is 20% of x = 0.20x
Maintenance of B is 20% of y = 0.20y
Maintenance of C is 25% of z = 0.25z
0.20x + 0.20y + 0.25z = 345
Multiplying by 100 we get
20x + 20y + 25 z = 34500
Dividing by 5 we get
4x + 4y + 5z = 6900 .......(2)
Monthly fee of A is 10% of x = 0.10x
Monthly fee of B is 20% of y = 0.20 y
Monthly Fee of C is 10% of z = 0.10z
Now
0.10x + 0.20y + 0.10 z= 1820 - 1600
0.10x + 0.20y + 0.10z = 220
Multiplying by 100 we get
10x + 20y + 10z = 22000
Dividing by 10
x + 2y + z = 2200 ....(3)
Making a Matrix of equation (1), (2) & (3)
![\left[\begin{array}{ccc}1&1&1\\4&4&5\\1&2&1\end{array}\right] \left[\begin{array}{c}x\\y\\z\end{array}\right] =\left[\begin{array}{c}1600\\6900\\2200\end{array}\right]](https://tex.z-dn.net/?f=%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%261%261%5C%5C4%264%265%5C%5C1%262%261%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5Cz%5Cend%7Barray%7D%5Cright%5D%20%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D1600%5C%5C6900%5C%5C2200%5Cend%7Barray%7D%5Cright%5D%20%20%20)
is the required matrix
Answer:
25151/100000
Step-by-step explanation: