Answer:
Solve the equation.
h
=
S
−
l
w
w
+
l
Step-by-step explanation:
(2, 0)
(–1, –5)
(3, 25)
2.on which of the following lines does the point (7, 1) lie
A. y - 5x = 4
B.y = x - 10
C. y=-4x + 3
D. y= -x + 8
3.Find the slope of the line through (-9, -10) & (-2, -5)
A -5/7
B 7/5
C 5/7
D -7/5
Answer:
The original price was $5
Step-by-step explanation:
100% - 40% = 60% =0.6
So the discounted price is 60% of the original price
3 = 0.6 X
30 = 6x
x = 5
Answer
Find out the speed of the boat in still water .
To proof
Let us assume that the speed of the boat in still water be u .
As given
The speed of a stream is 4 mph
hence
speed upstream = u - 4
speed downstream = u + 4
Formula
As given
A boat travels 8 miles upstream in the same time it takes to travel 16 miles downstream.
First case for the upstream
Second case for the downstream
now compare the equations
simplify the equation
8( u +4 ) = 16 (u -4)
8u +32 = 16u - 64
8u = 96
u = 12 mph is the speed of the boat in still water .
Hence proved
The speed of the stream = 4 mph.
Let us assume speed of the boat in still water = x mph.
Total speed upstream = (x-4) mph.
Total speed downstream = (x+4) mph.
We know, time, speed and distance relation.
Time = Distance / Speed.
Total time taken upstream = 8 / (x-4)
Total time taken downstream = 16/(x+4).
Time taken upstream = time taken downstream.
Therefore,
8 / (x-4) = 16/(x+4).
On cross multiplication, we get
16(x-4) = 8(x+4).
16x - 64 = 8x +32.
Adding 64 on both sides, we get
16x - 64+64 = 8x +32+64
16x = 8x + 96.
Subtracting 8x from both sides, we get
16x-8x = 8x-8x + 96.
8x = 96.
Dividing both sides by 8, we get
x = 12.