7r=-7/2
divide both sides by 7 to get r by itself
(7r)/(7) = (-7/2)/(7)
if you don't quite see it, think of multiplying both sides by 1/7 instead (its the same thing as dividing by 7)
(7r)*(1/7)=(-7/2)*(1/7)
r=-1/2
Answer:
Item (D)
Step-by-step explanation:
In the stratified random sample we would divide our population into homogeneous groups / strata and then we randomly select the individuals in each group / stratum.
In general, when comparing with the simple random sample, we realize that stratified random sampling has the advantage of increasing accuracy and decreasing variability.
In the question, we have two strata: female students and male students. On each one of the strata, a random sample of 25 names was made in the list.
It should be A
Angle b=angle g
6x+8=4x+12
2x=4
The total number of pencils is 2,160. When estimating to the nearest hundredth one gets 2,200, which is an underestimate.
The advantage of underestimating is that your answer is more accurate than an overestimate.
Represent the length and width by L and W. Then L = W + 4.
Using the perimeter formula: P = 2L + 2W = 68 ft = 2W) + 2(W+4).
Solve for W: 68 = 2W + 2W + 8, or 4W = 60. Thus, W = 15 and L = 19.
The dimensions of the rectangle are 15 by 19 feet.
