Answer:
The expression that shows how long the two machines will operate simultaneously is:

Step-by-step explanation:
We know that:
x: hours to manufacture a deck of cards for machine A
y: hours to manufacture a deck of cards for machine B
z: hours that machine A operates alone
The number of decks manufactured only by machine A is:

So, the remaining decks are given by:

Then, the combined rate of machines A and B would be:

The work-rate formula is:

Hence, the time that the two machines work simultaneously is:


Answer:
x = -7
How to:
Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation
5°x-(2°x-9)=0
Pull out like factors:
21 + 3x = 3 • (x + 7)
Equations which are never true: Solve 3 = 0
<em>Solving a Single Variable Equation:</em>
Solve : x+7 = 0
Subtract 7 from both sides of the equation : x = -7
hello :<span>
<span>an equation of the circle Center at the
O(a,b) and ridus : r is :
(x-a)² +(y-b)² = r²
in this exercice : a =0 and b = 0 (Center at the origin)
r = AO
r² = (AO)²
r² = (4-0)² +(5-0)² = 16+25=41
an equation of the circle that satisfies the stated conditions.
Center at the origin, passing through B(4, 5) is : x² +y² = 41</span></span>
x² +y² - 41=0