Answer:
2. x
² + y
²
= 4
3. x² + y² = 23
Step-by-step explanation:
The equation of a circle with center
(
a
,
b
) and radius r is:
(
x
−
a
)²
+ (
y
−
b
)
² = r
²
Explanation:
Here,
a
=
0
, b
=
0
, r
=
2
The equation is:
(
x
-0
)
² + (
y
-0
)
² = (
2 )
²
that is: x
² + y
² = 4
Thus:
x
² + y
²
= 4
3. Each point on a circle has the same distance from the center. This distance is the radius r of the circle.
Here,
(
-3
,
4
) is a point on the circle, meaning that the radius of the circle is the distance between (
0
,
0
)
, the center, and (
-3
,
4
)
.
thus a circle centered on the origin will have an equation of:
x² + y² =r²
And, (
-3
,
4
) lies on the circle, we have:
(-3)² + (4)² = r²
9 + 14 = 23
substituting;
x² + y² = 23
180/10=18 is one but the easitest way is with tens or hundreds
Answer:
380.13
Step-by-step explanation:
area= (pi)x(r^2)
pi times r squared
Answer:
y = - 400 + 700x
Step-by-step explanation:
Nour's altitude increased at a constant rate from the Dead Sea up to Amman.
Initially, her altitude was 400 meters below from the sea level and then she arrived at an altitude was 1000 meters above sea level arrived to Amman, 2 hours later.
So, she moves (400 + 1000) = 1400 meters in 2 hours.
Therefore, her rate of change of altitude is 
meters per hour.
Therefore, if y represents Nour's altitude in meters relative to the sea level after x hours then the relationship between the altitude and number of hours is given by
y = - 400 + 700x (Answer)
Answer:
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