Must be 16 and 21 because we can see
30 and 70 has 10 as factor
24 and 44 has 2 as factor
12 and 30 has 2 as factor and all those factors are greater than one
p-6p+7=3(2p-3)-4(-10+4p
We move all terms to the left:
p-6p+7-(3(2p-3)-4(-10+4p)=0
We add all the numbers together, and all the variables
p-6p-(3(2p-3)-4(4p-10)+7=0
We add all the numbers together, and all the variables
-5p-(3(2p-3)-4(4p-10)+7=0
7) Certainly there is a typo in the statement, just see that the expression of item (ii) is different from that of item (i). Probably the correct expression is:

. With this consideration, we can continue.
(i) Let E the expression that we are analyzing:

Since (x-1)² is a perfect square, it is a positive number. So, E is a result of a sum of two positive numbers, 2(x-1)² and 3. Hence, E is a positive number, too.
(ii) Manipulating the expression:

So, it's the case when E=0. However, E is always a positive number. Then, there is no real number x that satisfies the expression.
8) Let E the expression that we want to calculate:

Multiplying by (2-1) in the both sides:

Repeating the process, we obtain:
The experimental probability changes every time he rolls the die but if its just the next roll he has a 1/6 chance of getting a 3
He put in the value of x into y
and the value of y in x
if that confuse you here this is what it will look like
(x,y)->(y,x)