It would be B. I took a test with this
Answer:

Step-by-step explanation:
Hi there!

We're given that x=4 and y=12. Plug these in:

I hope this helps!
Answer: 10y^4
Since it can go 10y^4(3y^4+1)
Step-by-step explanation:
Answer:
36 & 54
Step-by-step explanation:
<em><u>By </u></em><em><u>Question</u></em><em><u> </u></em><em><u>:</u></em><em><u>-</u></em><em><u> </u></em>
- Sum of numbers = 90 .
- Difference of numbers = 18 .
<em><u>Let </u></em><em><u>:</u></em><em><u>-</u></em><em><u> </u></em>
- First Number be x .
- Second number be y .
<em><u>According</u></em><em><u> to</u></em><em><u> </u></em><em><u>1</u></em><em><u>s</u></em><em><u>t</u></em><em><u> </u></em><em><u>condition</u></em><em><u> </u></em><em><u>:</u></em><em><u>-</u></em><em><u> </u></em>
x + y = 90
<u>According</u><u> to</u><u> </u><u>2</u><u>n</u><u>d</u><u> </u><u>condition</u><u> </u><u>:</u><u>-</u><u> </u>
x - y = 18
<em><u>Adding</u></em><em><u> the</u></em><em><u> </u></em><em><u>equations</u></em><em><u> </u></em><em><u>:</u></em><em><u>-</u></em><em><u> </u></em>
2x = 18 + 90
2x = 108
x = 54
<em><u>Therefore</u></em><em><u> </u></em><em><u>:</u></em><em><u>-</u></em><em><u> </u></em>
First number = 54
Second number = 36
When simplified the answers results in
= -1