X= -b⁺₋ √b²-4ac/2a
x= (-(-2)⁺₋√(-2)²- 4(4)(-5))/2(4)
x= 4 ⁺₋√4+80/8
x= (4⁺₋ 9.165)/8
x= 4+9.165)/8 or x= 4-9.165)/8
x= 1.40 or x= -0.896
Answer:
D. Mean absolute deviation
Step-by-step explanation:
Median gives us : 159
Range gives us: 680 - 127 = 553
mean gives us :
127+137+159+188+680 = 1291
1291 / 5
= 258.2
MAD gives us the mean deviation (avg change from the mean):
mean
= 258.2
258.2 - 127 =131.2
258.2 - 137 =121.2
258.2 - 159 =99.2
258.2 - 188 =70.2
680 - 258.2
=421.8
Find the mean of the variances:
70.2+99.2+121.2+131.2+421.8 = 843.6
843.6 / 5
= 168.72
Mad = 258.2 +- 168.72
The rule is that :
B. The product of the means is equal to the product of the extremes
Answer: I think it is -2.30
