Use Photomath for the answers :)
Answer:
y=13
Step-by-step explanation:
if x=20 when y=8 (we can creat equation )
x=2y+4 (you can prove that the equation is correct by substitute )
so the question is if x=30 find the value of y
30=2y+4
30‒4=2y
26=2y
26/2=2y/2
13=y
i hope this helps you
Answer:
5 (probably not right i havent done this type of math in a long time)
Step-by-step explanation:

<em><u>Solution:</u></em>
Given that,

We have to factor out terms and write as a product of 2 binomials and monomial
A monomial is a mathematical expression with only one term, while a binomial is a mathematical expression with two terms.
From given expression,

3 and a are common factors in second bracket

Hence, the product of two binomial is written in two binomial and a monomial
C
Because .75 times 9 would give you the price of the books and then you would have to add C, the amount left to get to 20.