Answer:
5
Step-by-step explanation:
-5 + 5 = 0
Answer:
sorry don't know i just need points
GOOD LUCK
me and my friend are seeing who can get more points
Answer:
a) No.
b) Yes.
Step-by-step explanation:
a) It's not proportional. Although the graph represents a straight line, it does not pass through the origin (0,0).
b) It is proportional. It is a straight line that passes through the origin.
<span>6 km × 1 hour/(b-4 km) = 12 km × (1 hour/(b+4 km)
6/(b-4) hours = 12/(b+4) hours
6(b+4) = 12(b-4)
6b + 24 = 12b - 48
72 = 6b
b = 12
The boat's speed in still water is 12 km/hour.</span>
Surface area is just the area of all these 4 triangles plus the rectangle.
First we can find the area of the rectangle.

Half of the length is 28 cm, so the full length must be 28 * 2 = 56 cm.


The base for the left and right triangles are 27. The heights would be the net length minus half the length of the rectangle:

Calculate the area:



We have two of these triangles.

Now do the other two pair of triangles. The bases for them are 28 + 28 = 56 cm. The heights would be the net width minus the width of the rectangle:

Now find the area:



We have two of these triangles.

Add all the areas together: