Answer:
B
Step-by-step explanation:
A. these simply to 21 + 7x and 21 + 3x
- this one is incorrect because the 7x and 3x are different
B. these simplify to 10 + x and 10 + x
- this is the correct one since they are exactly the same
C. these simplify to 21x and 7x + 21
- these two are not the same because one expression has only a number with a variable but the other one has a number with a variable <em>and </em>another number
D. these simplify to
and 
- in subtraction, the order of the 3 and the x matters, so the equations are not the same
- example: 6 - 4 = 2 but 4 - 6 = -2
It is: x + 27 = -12
x = -12 - 27
x = -39
In short, Your Answer would be -39
Hope this helps!
Answer:
$16.25 $15.95 $15.75
Step-by-step explanation:
because a 15% tip is $3.00
Answer:

Step-by-step explanation:
let a be the number of tennis balls.
let b be the number of tennis rackets.
We write determine the ratio of balls to rackets by dividing the number of balls by the number of rackets:

For every one ball, there 5 thirds of a racket.
We plot this function on a graph to visualize our model;