All you have to do, is combine like terms. Let's go through it:

Arrange it so you can easily combine like terms:

So, your answer for the sum is 1) 7x² - 10x + 2
5/6 is always going to my equal to itself. o divide the two and see what you get
Answer: The numbers are decreasing by 2. So that means that the eighteenth number would be -29.
Explanation:
{5, 3, 1, -1, -3, -5, -7, -9, -11, -13, -15, -17, -19, -21, -23, -25, -27, -29...}
If you add a zero at the end it is easier to understand. 0.20 > 0.18 because 20 is greater than 18
<u>Question 7:
Define x :
</u>
Let the digit in the ones place be x.
The digit in the tens place is x+2.
The sum of the digit and its reverse is 66
<u>Find x:</u>
10(x + 2) + x + 10x + (x + 2) = 66
10x + 20 + x + 10x + x + 2 = 66
22x + 22 = 66
22x = 44
x = 2
<u>Find the number:</u>
The number in the ones place = x= 2
The number in the tens place = x = 2 + 2 = 4
Answer : The number is 42.
<u>Question 8:</u>
<u>Define x:</u>
Let the digit in the tens place be x.
The digit in the ones place is x+7.
The number = 10x + x + 7 = 11x + 7
If the digit interchange,
the number = 10(x + 7) + x = 10x + 70 + x = 11x + 70
<u>Find x:
</u>
9(11x + 7) = 2(11x + 70)
99x + 63 = 22x + 140
99x - 22x = 140 - 63
77x = 77
x = 1
<u>Find the number:
</u>
x = 1
x + 7 = 1 + 7 = 8
So the number is 18
Answer: The number is 18.