4 1/2
Try Cymath it’s great for this stuff
It's slope would be undefined.
and 
use the second expression to calculate the left-hand side of the first equation:

Add 10 to both sides if this equation to get

and divide both sides by 2

this proves that x = 17, give the two initial equations
Answer:

Step-by-step explanation:
Given
per hour for 40 hours, weekly
per hour over 40 hours, weekly
Required
Determine f(x)
From the question, we have that
x represents hours worked
Earnings in 40 hours is: 40 * 10 = $400
Hours over 40 will be: x - 40
So, earnings during this time will be: (x - 40) * 15
Total earnings is:




There are 3 rectangles.
In the plane, each rectangle has 2x + 7 horizontal side.
The fence covers 3 horizontal sides => 3 (2x + 7)
In the plane, the vertical sideis x. And the fence covers 4 vertical sides => 4x
Then the total amount of fecncin is: 3(2x+7) + 4x = 6x + 21 + 4x = 10x + 21
Answer: 10x + 21<span> </span>