Answer:
a>4 or a < 8
Step-by-step explanation:
We can start with the inequality on the left
-a + 2(4+3a) > 28
expand using the distributive property
-a + 8 + 6a > 28
5a + 8 > 28
subtract 8 from both sides to isolate the variable and its coefficient
5a > 20
divide both sides by 5 to isolate a
a > 4
moving on to the inequality on the right
2a - (3a+4) > -12
treat the minus sign as a -1
2a + (-1)(3a+4) > - 12
expand
2a - 3a - 4 > - 12
-a - 4 > -12
add 4 to both sides to isolate a and its coefficient
-a > - 8
multiply both sides by -1 but change the sign because we are multiplying by a negative number
a < 8
A.
Circumference = π * diameter or
π * 2*radius (diameter = 2 * radius).
So you would divide by π to get the diameter, then divide by 2 to get the radius. So A.
Answer:
C
Step-by-step explanation:
28 each book 155-15=140 and then 140÷5=28
Answer:

Step-by-step explanation:
As the given Augmented matrix is
![\left[\begin{array}{ccccc}9&-2&0&-4&:8\\0&7&-1&-1&:9\\8&12&-6&5&:-2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D9%26-2%260%26-4%26%3A8%5C%5C0%267%26-1%26-1%26%3A9%5C%5C8%2612%26-6%265%26%3A-2%5Cend%7Barray%7D%5Cright%5D)
Step 1 :
↔
![\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&7&-1&-1&:9\\8&12&-6&5&:-2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%26-14%266%26-9%26%3A10%5C%5C0%267%26-1%26-1%26%3A9%5C%5C8%2612%26-6%265%26%3A-2%5Cend%7Barray%7D%5Cright%5D)
Step 2 :
↔
![\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&7&-1&-1&:9\\0&124&-54&77&:-82\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%26-14%266%26-9%26%3A10%5C%5C0%267%26-1%26-1%26%3A9%5C%5C0%26124%26-54%2677%26%3A-82%5Cend%7Barray%7D%5Cright%5D)
Step 3 :
↔
![\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&124&-54&77&:-82\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%26-14%266%26-9%26%3A10%5C%5C0%261%26-%5Cfrac%7B1%7D%7B7%7D%20%26-%5Cfrac%7B1%7D%7B7%7D%20%26%3A%5Cfrac%7B9%7D%7B7%7D%20%5C%5C0%26124%26-54%2677%26%3A-82%5Cend%7Barray%7D%5Cright%5D)
Step 4 :
↔
,
↔
![\left[\begin{array}{ccccc}1&0&4&-11&:-8\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&0&- \frac{254}{7} &\frac{663}{7} &:-\frac{1690}{7} \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%260%264%26-11%26%3A-8%5C%5C0%261%26-%5Cfrac%7B1%7D%7B7%7D%20%26-%5Cfrac%7B1%7D%7B7%7D%20%26%3A%5Cfrac%7B9%7D%7B7%7D%20%5C%5C0%260%26-%20%5Cfrac%7B254%7D%7B7%7D%20%26%5Cfrac%7B663%7D%7B7%7D%20%26%3A-%5Cfrac%7B1690%7D%7B7%7D%20%5Cend%7Barray%7D%5Cright%5D)
Step 5 :
↔
![\left[\begin{array}{ccccc}1&0&4&-11&:-8\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&0&1&-\frac{663}{254} &:-\frac{1690}{254} \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%260%264%26-11%26%3A-8%5C%5C0%261%26-%5Cfrac%7B1%7D%7B7%7D%20%26-%5Cfrac%7B1%7D%7B7%7D%20%26%3A%5Cfrac%7B9%7D%7B7%7D%20%5C%5C0%260%261%26-%5Cfrac%7B663%7D%7B254%7D%20%26%3A-%5Cfrac%7B1690%7D%7B254%7D%20%5Cend%7Barray%7D%5Cright%5D)
Step 6 :
↔
,
↔
![\left[\begin{array}{ccccc}1&0&0&-\frac{71}{127} &:\frac{176}{127} \\0&1&0&-\frac{131}{254} &:\frac{284}{127} \\0&0&1&-\frac{663}{254} &:\frac{845}{127} \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccccc%7D1%260%260%26-%5Cfrac%7B71%7D%7B127%7D%20%26%3A%5Cfrac%7B176%7D%7B127%7D%20%5C%5C0%261%260%26-%5Cfrac%7B131%7D%7B254%7D%20%26%3A%5Cfrac%7B284%7D%7B127%7D%20%5C%5C0%260%261%26-%5Cfrac%7B663%7D%7B254%7D%20%26%3A%5Cfrac%7B845%7D%7B127%7D%20%5Cend%7Barray%7D%5Cright%5D)
∴ we get
