Answer:
14 books
Step-by-step explanation:
Let b = number of books at the beginning
She sold 1/2 of the books
b - 1/2 b
This is how many she had left
Then she bought 7
b - 1/2 b + 7
this equals 14
b - 1/2 b + 7 = 14
Combine like terms
1/2 b + 7 = 14
Subtract 7 from each side
1/2 b = 14-7
1/2 b = 7
Multiply each side by 2
1/2 b * 2 = 7*2
b = 14
She started with 14 books
Answer: I'm pretty sure its 3x+27
Step-by-step explanation: So all you have to do is multiply everything in the parentheses by 3. So you would do 3 times x and it would be 3x and then 3 times 9 which will get you 27. After you just put it back into a equation 3x+27
Answer:
x=m-a/12
the m-a should be over 12 as the numerator but it's hard to type it like that
Step-by-step explanation:
a+12x=m
12x=m-a
x=m-a/12
Answer:
40 girls
Step By Step Explanation:
assume boys = y girls = x
y = 1/2x + 10
y = 30
30 = 1/2x + 10
1/2x = 20
x = 20 *2 = 40
girls is 40 boys is 30
Answer: 10:10
Step-by-step explanation:
