Answer:
D
Step-by-step explanation:
It's one of each or not both tho:)
Answer:
1st= 47/7 or 6.71
2nd= 48/7 or 6.857
Step-by-step explanation:
1st number =X and 2nd number = Y
According to question, X+7=2Y
20+Y=4X
X=2Y-7 (from 1st condition)
putting in it second
20+Y=4(2Y-7)
20+Y=8Y-28
20+28=8Y-Y
48=7Y
Y=48/7
so X=2(48/7)-7
=96-49/7
47/7
Answer:

Step-by-step explanation:
![\dfrac 12 \left[\sin(a+b)+\sin(a-b) \right]\\\\\\=\dfrac 12\left[ 2 \sin a \cos b\right]\\\\\\=\sin a \cos b](https://tex.z-dn.net/?f=%5Cdfrac%2012%20%5Cleft%5B%5Csin%28a%2Bb%29%2B%5Csin%28a-b%29%20%5Cright%5D%5C%5C%5C%5C%5C%5C%3D%5Cdfrac%2012%5Cleft%5B%202%20%5Csin%20a%20%5Ccos%20b%5Cright%5D%5C%5C%5C%5C%5C%5C%3D%5Csin%20a%20%5Ccos%20b)
54+x=12+3x
X=21 =number of classes
Total amount she will pay is $75