Answer:
The first one
Step-by-step explanation:
<span>{x | x I, x ≤ 0}
because I is the Integers</span>
To find this answer, we need to multiply 3.57 by 12.

Therefore, 12 planks will cost $42.84.
The first answer.
Point P is at (50,-40) the distance from Q to P is 80 units which you can find by subtracting the x of Q (-30) from the x of P (50).
50-(-30)=80
It then tells you point R is vertically above point Q so you know your x value for R will be the same as Q.
Add your distance from Q to P of 80 units to the y value of Q because you are traveling up.
-40+80=40
R will have a point of (-30,40) and a distance of 80 units
Answer:
X = 5
Step-by-step explanation:
Here is what I am picturing (not to scale)
A ----------------B-----------C
We are given the information of AB (which equals 3x + 1), BC (which equals 4x - 5), and AC (which equals 8x - 9).
With reference to the line, AB + BC = AC
So,
3x + 1 + 4x - 5 = 8x - 9
7x - 4 = 8x - 9
5 = x