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.
Answer: 1.) x - 2y = 4 , add 2y to both sides. ---> answer is, X = 2y + 4
2.) 2x - 6y = 8, Add 6y to both sides, then divide both sides by 2. --> answer is, X = 3y + 4
27; The first stack is 3 x 3 (= 9). You then multiply 9 by 3 (for each of the 3 stacks). Basically, 3 x 3 x 3.
Answer:
24, 14
Step-by-step explanation:
x + y = 38
x = 10 + y
You can substitute (10+y) into the top equation where the x is.
10 + y + y = 38
10 + 2y = 38
2y = 28
y = 14
Now plug 14 in for y in either equation to get x
x = 10 + 14
x = 24
Answer:
The answer is 5
Step-by-step explanation:
First arrange the numbers in order :
2, 2, 4 ,5, 7, 7, 7
Then find the middle number :
5
The middle number is 5 , therefore the answer is 5.