9 × n - 20 = 16
9n - 20 = 16
+ 20
9n = 36
÷ 9
n = 4
Hope this helps! :)
Multiply everything in the parenthesis by a.
ac + ab = d
Subtract ab from both sides.
ac = d - ab
Divide a on both sides.
c = d - ab / a
Hope this helps!
Answer:
She worked for 6 hours on Saturday.
Step-by-step explanation:
Number of hours worked by Danielle last week = 18.25 hours
She worked for three days, Monday, Wednesday and Saturday.
Let she worked on Saturday = x hours
Therefore, total hours worked by Danielle in three days = 6.5 + 5.75 + x
And the equation will be,
6.5 + 5.75 + x = 18.25
12.25 + x = 18.25
x = 18.25 - 12.25
x = 6
Therefore, she worked for 6 hours on Saturday.
X/4-9=5
x/4=14
x=14/4
x=7/2
x=3.5
Answer:
<em>9*364 - 9*125 - 9*39 = 1,800</em>
Step-by-step explanation:
<em>Mental Calculation</em>
If we detect known patterns in the calculations, we could easily give their results without the use of calculators.
We are given the expression to evaluate:
9*364 - 9*125 - 9*39
The first thing to note is the 9 is a common factor of all terms, thus we take it out:
9*(364 - 125 - 39)
The negative numbers can be easily added
125
+ 39
------------
164
Now our expression is much easier:
9*(364 - 164)
The subtraction of 364-164 is 200, thus the result of the operations is:
9*200. We only need to recall 9*2=18 and add two zeros to get 1,800, thus:
9*364 - 9*125 - 9*39 = 1,800
