The answer is 54 hope this helps
Answer:
x < -4 or x > 7.
Step-by-step explanation:
We first determine the critical points by solving x^2 - 3x - 28 = 0:
x^2 - 3x - 28 = 0
(x - 7)(x + 4) = 0
x = 7, - 4
so the critical points are -4 and 7.
Create a Table (pos = positive and neg = negative):
Value of x< - 4 -4 < x < 7 x > 7
---------------------|----------- |--------------------- |---------------------
x + 4 NEG POS POS
x - 7 NEG NEG POS
(x + 4)(x - 7) POS NEG POS
So the function is positive (>0) for x < -4 or x > 7.
You can also do this by drawing the graph of the function.
19.25 (tax)
294.25 (total price)
135.75 (money left)
REASONING:
In this word problem it says Anna has 430 dollars. The phone costs 275 dollars. It also says that when she buys the phone, she will have to pay a tax of 7%.
To find how much tax she will pay, we must do [275] x [0.07]
After inputting this into a calculator, you will get 19.25 (tax)
To find the total price, all you have to do is add 19.25 to 275. When you do this, you will get 294.25 dollars (total price)
To find how much money she has left,
430-294.25=135.75 (money left)
Remark
Let the pigs = p
Let the chickens = c
Givens
30 heads is another way of saying that there were 30 creatures in the barnyard. In addition each chicken has 2 legs and each pig has 4
c + p = 30
2C + 4P = 100 (2) Divide (2) by 2
C + 2P = 50 (3) Subtract (1) from (3)
<u>C + P = 30</u>
P = 20
So there were 20 pigs.
