Because these are not like terms, they cannot be combined. The variables are different, that's what makes them not like terms
Answer:
The marked up percentage is 112.5%
Step-by-step explanation:
The cost price of the emerald pendant = $400
The selling price of the emerald pendant = $840
Now, the Mark up Price = Selling Price - Cost Price
= $840 - $400 = $450
Also, 
= 
⇒ Percentage of Mark up Price = 112.5%
Hence, the marked up percentage is 112.5%
Step-by-step explanation:
2x-y=8
x+y=20
------------
3x=28
×=28÷3=9.3
so
9.3+y=20
y=20-9.3
y=20.7
Answer:
8500 ft²
Step-by-step explanation:
First we need to find the area of the non shaded region within this shaded region. To find the area of this non shaded rectangle, use the formula base×height.
20×100=2000 ft².
Now we need to find the height and width of the shaded region which is,
25+25+20=70 Height
25+25+100=150 Width
mutiply these numbers 150×70=10500 ft²
Now we just need to subtract that inside area.
10500-2000=8500 ft²
10 x 10 = 100 80 x 80 =6400 6400-100= 6300 so that would have to be 3150ft.