Answer:
The two groups must be as similar as possible. They should be demographically homogeneous and have similar academic performance so as the only variable that is different is the one is tested (extra homework assigned)
Step-by-step explanation:
In this case the scientific method is using an experimental group (the 8th grade class that has extra homework problems) and a control group (the 8th grade class that has not extra homework problems) in order to prove if extra homework helps students learn algebra.
In order to be a valid experiments the two groups should present exactly the same characteristics, except for the variable studied, so they must be as homogeneous as possible.
Answer:
see below
Step-by-step explanation:
Angle ACE = DCE since they are vertical angles
Angle A = Angle E parallel lines cut by a transversal form congruent alternate interior angles
Angle B = Angle D parallel lines cut by a transversal form congruent alternate interior angles
When all three angles are equal, the triangles are similar.
We can use ratios to find DE
DE CE
------- = ----------
AB AC
DE 8
------- = ----------
12 10
Using cross products
10 DE = 8*12
10 DE = 96
Divide by 10
DE = 9.6
1/6 and 1/2.
Multiply them together you get 1/12.
Answer: 4/3
Step-by-step explanation:
First off, we should all get the denominators to be the same.
14 is the LCM of each of the denominators, so:
3x / 7 times 2/2 = 6x/14
-1/2 times 7/7 = -7/14
and 1/14 is 1/14
So now we have
6x/7 + -7/14 = 1/14
We can multiply everything by 14 to get rid of the denominator completely, which leaves us with:
6x - 7 = 1
Then we just solve like a normal equation:
6x = 8
x = 8/6 , or 4/3