Answer:
x=−16/7
Step-by-step explanation:
happy to help ya :)
Answer:
8.5 hours
Step-by-step explanation:
30 mins per page ( 15 )
so, 30 × 15 = 450
each hour is 60 minutes so 450 ÷ 60 = 7.5
then add the 1 hour that she already took to write the outline, so 8.5 hrs
Answer:
30 m/s
Step-by-step explanation:
Let's say the distance from the first car to the intersection is x, and the distance from the second car to the intersection is y.
The distance between the cars can be found with Pythagorean theorem:
d² = x² + y²
Taking derivative with respect to time:
2d dd/dt = 2x dx/dt + 2y dy/dt
d dd/dt = x dx/dt + y dy/dt
We know that x = 200, dx/dt = -25, y = 150, and dy/dt = -50/3.
To find dd/dt, we still need to find d.
d² = x² + y²
d² = (200)² + (150)²
d = 250
Plugging everything in:
250 dd/dt = (200) (-25) + (150) (-50/3)
dd/dt = -30
The cars are approaching each other at a rate of 30 m/s at that instant.
A). |x| = |-x|
This is always true.
The definition of 'absolute' value is 'size of the number without its sign'.
That's what this expression says.
b). |x| = -|x|
This is never true, because an absolute value is never negative.
This one would true if x=0 . So maybe some people might say
it's sometimes true, but that doesn't feel right to me. I say never.
c). |-x| = -|x|
This looks to me like exactly the same situation as (b),
and I would say all the same things about it.
The correct answer is it is a figure with at least 3 straight sides. When you think of a square or a triangle they both have at least 3 sides that are straight. A circle doesn't have any straight sides so it is not a polygon.
You can prove that the other answer is wrong because of two things:
The definition of a polygon is a plane figure with at least three straight sides.
Also, when you think of most shapes what do they all have in common? The have at least three straight sides
