Answer:
The answer is D. Hope this helps
Scientific notation is
x*10^y such that
1<u><</u>x<10
780=7.8 times 100=7.8 times 10^2
7.8*10^2
6+9x=456
Subtract 6 from both sides
6-6+9x = 456-6
9x = 450
Divide each side by 9
X = 50
Plug it in 6+9(50) = 456
6+450 = 456
Length of the window = 9ft
The length is x feet more than the height
Therefore, the height is (9-x) ft
