Answer:
b = 13
Step-by-step explanation:
the value of the discount is a constant, while the total cost of the books is a variable because it depends of the purchase
We can write this equation
5b - 7 = 58
Solve it
1) add 7 at both members
5b -7 + 7 = 58 + 7
5b = 65
2) divide both membera by 5
b = 13
Answer:
10
Step-by-step explanation:

The starting equation is
100=S+D+K
S is for Sarah, D is for Dave, and K is for Kate
This is what we know:
S=15+D
and
K=D-5
Now that we know how to find the values of everything, we must plug it in.
100=(15+D)+D+(D-5)
Combine like terms.
100=10+3D
Subtract 10 to isolate variable.
90=3D
Divide by 3 to isolate variable.
30=D
Plug in number to find the answers.
Answer:
Sarah worked for 45 hours
Dave worked for 30 hours
Kate worked for 25 hours
Answer:
-3
Step-by-step explanation:
The slope of a line can be calculated with the formula (y2-y1)/(x2-x1)
In this case we have:
(-4-(2))/(7-5)
(-6)/(2)
-3
Let me know if this helps!