Hi there! 5 bottles of water for $3 would make $0.60 per bottle. 0.6 * 15 = 9. That means 15 bottles of water should equal $9, but instead it is $8. Based on that, no. The costs for bottles of water is not proportional to the numbers sold. Basically, you can divide to find unit prices and multiply the number of another item to see if the numbers are proportional.
One “x” tile and five “1” cubes
Use the identity
sec^2x = 1 + tan^2 x
- so sec x = sqrt(1 + tan^2 x) then:-
tan x + sqrt( 1 + tan^2 x) = 1
sqrt ( 1 + tan^2 x) = 1 - tan x
1 + tan^2 x = 1 + tan^2x - 2 tan x
0 = -2 tanx
tan x = 0
x = 0, π
π is an extraneous root because sec 180 = -1
So the answer is 0 degrees