-3 because it reduced -3 every hour of you divide -12 by 4 you will get -3 which is the average
Answer:
10 km/hr
Step-by-step explanation:
Average speed = Total distance travelled / Total time taken
Ardi:
Total distance travelled = 70 km
Total time taken = 35 minutes = 35/60 hour
Average speed = Total distance travelled / Total time taken
= 70 km ÷ 35/60 hr
= 70 × 60/35
= 4,200/35
= 120 km/hr
Lei:
Total distance travelled = 585 km Total time taken = 9:05 - 13:35 = 4 hours 30 minutes
= 4.5 hours
Average speed = Total distance travelled / Total time taken
= 585 km / 4.5 hours
= 130 km/hr
Difference, in km/h, between the average speed of their trains = Lei's train - Ardi's train
= 130 km/hr - 120 km/hr
= 10 km/hr
Answer:
Step-by-step explanation:
1.
Area of shaded region = Area of external rectangle - Area of internal rectangle
2.
Let the width of the rectangle be x inches.
Therefore, length of the rectangle = (x + 3) inches
A.
Area of rectangle
B.
Width of rectangle = 4 inches
Length of rectangle = 4 + 3 = 7 inches
Area of rectangle = 7*4 = 28 square inches.
In this equation x is equal to 5/26.
Answer:
(a) y = 9/4x -1/4
(b) (-2, -2), (-2, 2)
(c) see below
Step-by-step explanation:
(a) The derivative can be found from ...
2y·y' = 3x² +6x
At (x, y) = (1, 2), this is ...
4y' = 9
y' = 9/4
so the equation of the tangent is ...
y = (9/4)(x -1) +2
y = (9/4)x -1/4
__
(b) At y' = 0, we have ...
0 = 3x² +6x = 3x(x +2)
This says y' = 0 at x=0 or x=-2. (x = 0 is an extraneous solution.)
At x = -2, we have ...
y² = (-2)³ +3(-2)² = -8+12 = 4
y = ±2
So, the horizontal tangent points are (x, y) = (-2, ±2).