Answer:
Step-by-step explanation:
Given that,
|P| = 2x / 5 + 1
|Q| = x + 1
|P+Q| = 3x + 2
We know that, from Cauchy inequalities
|P| + |Q| > |P+Q|
(2x / 5) + 1 + x + 1 > 3x + 2
(2x / 5) + 2 + x > 3x + 2
Multiply through by 5
2x + 10 + 5x > 15x + 10
Collect like terms
2x + 5x - 15x > 10 -10
-8x > 0
Then,
Divide both side by -8, since we are dividing with a negative number the inequality sign will change
Then,
x < 0 first condition
Note that,
|P| > 0
Then,
2x / 5 + 1 > 0
2x / 5 > -1
2x > -5
x > -5/2
Also,
|Q| > 0
x + 1 > 0
x > -1
Also
|P+Q| > 0
3x + 2 > 0
3x > -2
x > -2 / 3
So, comparing the four conditions
We see that x ranges from -5/2 to 0, this range covers all the other ranges
(-5/2, 0)
The first answer is correct
Answer:
Step-by-step explanation:
The number is 49, First do 21 / 3 to find what 1/7 of the number is. We get 7, so we know 1/7 is 7 so if we do 7 x 7 we will have 7/7 or one whole and 7x7 is 49. Hope this helps
Answer: 104 pages
Step-by-step explanation:
On 1/4 is actually 2/8 so on Monday and Wednesday together she read 3/8 + 2/8 = 5/8 of the 352 pages and 5/8 x 352 = 220.
Tuesday she read 28 pages so she has read 220 + 28 = 248 pages.
She must read 352 -248 = 104 pages more