Answer:
Equation: 1.5s + 20 = 200
How long it will take for Samantha to finish a 200 meter race: 120 seconds
Step-by-step explanation:
The problem says Samantha walks at a rate of 1.5 meters per second. If we let "s" represent seconds, then we can write this as 1.5s. Since she gets a 20 meter head start, you can then write the equation as 1.5s + 20. Finally, its says use this equation to find how long it would take to finish a 200 meter race. So you set the previous equation equal to 200. Or 1.5s + 20 = 200.
To solve for "s" and find how long it would take to finish a 200 meter race, you first subtract 20 from each side. You should be left with 1.5s = 180. Then divide by 1.5. 180/1.5 equals 120. So it will take Samantha 120 seconds to finish the 200 meter race.
Answer:
<h2>0.</h2>
Step-by-step explanation:
First, we should line up the fractions.
6 / 7 - 6 / 7.
Second, we subtract straight across since denomionators are the same.
6 / 7 - 6 / 7 = 0.
Therefore, the difference is 0.
Answer:
EF = 20 cm
Step-by-step explanation:
Here, we want to find the length of EF
To do this, we use the principle of similar triangles
The similar triangles we are considering here will be ;
FEA and FBD
when two triangles are similar, the ratio of their corresponding sides are equal
Let us calculate DC first
we can use Pythagoras’ theorem here and it is that the square of the hypotenuse equals the sum of the square of the two other sides
Using the triangle EDC
15^2 = 12^2 + DC^2
DC^2 = 225-144
DC^2 = 81
DC = 9
So the entire length of BD is 9 + 12 = 21 cm
Thus, we have it that;
Let EF be x
so DF = 15 + x
Hence;
BD/DF = AE/EF
21/15+x = 12/x
21x = 12(15 + x)
21x = 180 + 12x
21x-12x = 180
9x = 180
x = 180/9
x = 20 cm
EF = 20 cm
Answer: The rate of change decreased.
Step-by-step explanation:
