21x + 28. just distribute the 7.
Answer:
Work shown below!
Step-by-step explanation:


Given:
The expression is:

To find:
Part A: The expression using parentheses so that the expression equals 23.
Part B: The expression using parentheses so that the expression equals 3.
Solution:
Part A:
In option A,

[Using BODMAS]

In option B,

[Using BODMAS]

In option C,


In option D,

[Using BODMAS]

After the calculation, we have
and
.
Therefore, the correct options are B and D.
Part B: From part A, it is clear that

Therefore, the correct option is C.
Answer:
406.67 miles
Step-by-step explanation:
250=28.95(4)+0.33m
250=115.8+.33m
134.2=.33m
134.2/.33=.33/.33m
m=406.666666667
rounded: m=406.67