Answer:
12 years old.
Step-by-step explanation:
1) 2x+x=18
2) Now solve 2x+x=18
Add alike terms
3x=18
Now divide both sides by 3 (3x/3 and 18/3)
x=6
So Hannah is 6 years old. Her sister must be 12.
Answer:
Marcus score is 13.7, the mean is 12.89, and the standard deviation is 1.95, so I’ll do ( 13.7 – 12.89)/ 1.95, Since Marcus' z-score is 0.415. The area to the left of the z-score is 65.9% so therefore Marcus did scored better than 65.9% of the students. So Marcus needs to score 98% better of all the other students in order for him to receive an actual certificate.
Step-by-step explanation:
Answer:
7987.1569 to the nearest thousandths is 7987.157
Step-by-step explanation:
I LOVE OUR SWEET MATCHLESS CHRIST JESUS!
Answer:
b)0, yes
Step-by-step explanation:
Given:
Vectors (4,8) . (6,-3)
Finding inner product of vectors:
= 4x6 + 8x-3
=24-24
=0
Now to check the angle between them using formula a.b=|a|.|b|cosθ
|a|= 
=8.9
|b|=
=6.7
Putting values of a.b=0 and |a|=8.9, |b|=6.7 in a.b=|a|.|b|cosθ we get,
0= 8.9(6.7)cosθ
cosθ =0
θ=90 degrees
Hence the two vectors are perpendicular !
