Answer:
option d is correct answer
Step-by-step explanation:
-18x+12
Let's review the options:
A. 169-26y+y^2 can be factorised into (13-y)(13-y)
B. 81+18y+y^2 can be factorised into (9+y)(9+y)
C. 64+8y+y^2 cannot be factorised into double brackets
D. 25+10y+y^2 can be factorised into (5+y)(5+y)
Therefore your answer is the odd one out, C.
The mean can be found by adding the two numbers and dividing by 2
let the second number be y
(x + y)/2 = 1/2x + 1
solve for y
multiply each side by 2
x + y = 2(1/2x + 1)
distribute
x + y = x + 2
subtract x on both sides
y = 2
ANSWER: the second number is 2
