The answer is A( +7) x (-5)
Answer:
The number of pages that Polina read was 90 and the number of pages that Marcus read was 18
Step-by-step explanation:
Let
x -----> number of pages that Polina read
y ----> number of pages that Marcus read
we know that
x+y=108 ----> equation A
x=5y -----> equation B
substitute equation B in equation A and solve for y

Find the value of x

therefore
The number of pages that Polina read was 90 and the number of pages that Marcus read was 18
Answer:
It's a valid sample because the first five people were selected to participate.
Step-by-step explanation:
True because random people who saw the advertisement responded. By chance, not every person who saw the advertisement answered, therefore it was random, but it would be more random if he decided to reject the second, fourth, sixth, and eighth person, and only the first, third, fifth, seventh, and ninth were chosen.
Answer:
x = 3
Step-by-step explanation:
3(x + 2) = 6(x - 1) + 3
Divide both sides by 3.
x + 2 = 2(x - 1) + 1
Distribute the 2 on the right side.
x + 2 = 2x - 2 + 1
Combine like terms on the right side.
x + 2 = 2x - 1
Add 1 to both sides. Subtract x from both sides.
3 = x
x = 3