So if the earth goes 18 miles per second you would multiply 18 and 60 since 60 seconds are in a minute. And that is 1,080 miles in a minute then times that by 5 and your answer is 5,400 miles in 5 minutes.
Let d(x) = 2x - 4
Or
y = 2x - 4
We have replace x = y
x = 2y - 4
Now Isolate "y"
x + 4 = 2y
Pass "2" dividing
(x + 4) / 2 = y
y = x/2 + 2
Or
d(x)^-1 = x/2 + 2
Let there be 2x science and 5x art books
<span>science books sold = 2x × 0.2 = 0.4x </span>
<span>science books unsold = 2x – 0.4x = 1.6x </span>
<span>art books sold = 5x × 0.2 = x </span>
<span>art books unsold = 5x – x = 4x </span>
<span>total books unsold = 1.6x + 4x = 5.6x </span>
<span>5.6x = 2240 </span>
<span>x = 400 </span>
<span>2x science = 800 </span>
<span>and 5x art books = 2000 </span>
