Answer:
The axis of symmetry of a parabola is a vertical line that divides the parabola into two congruent halves. The axis of symmetry always passes through the vertex of the parabola.
Step-by-step explanation:
I took algebra last year.
To find the mean of a set, add up all of the data points and divide by the number of data points.
For the first set:
(14+18+21+15+17) ÷ 5 = 85 ÷ 5 = 17
For the second set:
(15+17+22+20+16) ÷ 5 = 90 ÷ 5 = 18
To find the MAD (mean absolute deviation) of a set, find the mean of the distances of each data point from the mean.
For the first set:
(3+1+4+2+0) ÷ 5 = 10 ÷ 5 = 2
For the second set:
(3+1+4+2+2) ÷ 5 = 12 ÷ 5 = 2.4
To find the means-to-MAD ratio of a set, divide its mean by its MAD.
For the first set:
17 ÷ 2 = 8.5
For the second set:
18 ÷ 2.4 = 7.5
<span>50-8t<90
50-90<8t
-40<8t
8t>-40
t>-5
Solutions should go to the right.
Mary probably was solving it as following
</span>50-8t<90
<span>-8t<90-50
-8t<40 (here, when she divided both sides by -8, she had to change sign < to the sign >)
But she did not change the sign, and got
t<-5
</span>
