We will be using the formulas:
speed=distance/time
time=distance/speed
distance=speed×time
First let's find out Diane's rate of swimming. We can measure this by finding the slope (y/x) of a given coordinate on the graph. One point is (10,15), so you do 15/10=1.5m/s
Now for Rick's rate of swimming, just take a pair of values from the table. 12.5/10=1.25m/s
By the way m/s is metres per second for this
So at a constant speed of 1.5m/s, Diane swam 150m in 150/1.5= 100 seconds, or 1 minute 40 seconds
And at a constant speed of 1.25m/s, Rick swam 150m in 150/1.25= 120 seconds, or 2 minutes.
So the difference between their two times is 20 seconds
Answer:
First, you have to form simultaneous equation for both of their ages in yerms of a and b :
b = 4a - 12 -------- ( 1 )
a + b = 28 -------- ( 2 )
Next, you will have to solve it by substituting ( 1 ) into ( 2 ) :
a + (4a - 12) = 28
5a - 12 = 28
5a = 28 + 12
5a = 40
a = 8
Then, substitute a = 8 into ( 1 ) :
b = 4(8) - 12
b = 32 - 12
b = 20
Area of triangle is
A=b•h/2
A=(10x+5)(2x-5)/2
A=20x^2-50x+10x-25/2
A=20x^2-40x-25/2
A=2(10x^2-20x-12.5)/2
cancel 2 in numerator and denominator
A=10x^2-20x-12.5 in^2
Hope this helps
Answer:43 teaches
Step-by-step explanation:I research it
