X + 2y = -4
-x -x
2y = -x - 4
Divide all by 2
y = -x/2 - 2
y = (-1/2)x - 2
Answer:
Formula is 132 - 8n, and there are 52 windows on 10th floor.
Step-by-step explanation:
difference = 116-124 = -8 ( 8 less windows for every floor you go up)
the first fllor has 124 windows
Formula:

= 132 - 8n
10th Floor:

In dividing two equation with variables and exponent, First you must align or rearrange the equation and group them base on their variables but don't forget the sign of each variables. Second, proceed in dividing its quantity and then subtract its exponent to the other variables having the same. So by calculating it, the answer would be X or X^1
30% of 200=60 200+60= 260
Ty has £260
£260 x 2= £520
200+260+520= £980
Answer £980
I hope this is right :D