The angles of elevation and depression are formed by the line of sight and the horizontal line. When the line of vision is above the horizontal line, the angle is of elevation, and if the line of sight is below the horizontal, the angle is of depression.
The angle of depresion from the top of the taller building and the angle of elevation from the top of the shorter building are alternate interior angles. Then, if the angle of depression of the taller building is 15° the angle of elevation of the shorter building is 15° too. To understand this, you should see the diagram attached.
In the diagram you can notice that both angles, of elevation and depression, have the same value.
Then, the answer is:
The angle of depresion from the top of the taller building and the angle of elevation from the top of the shorter building are alternate interior angles.
To graph the equations, rewrite the equations written in standard form to slope-intercept form of the equation.
The easiest way to solve this comparison without any unusual comparisons is to find a common denominator for the two fractions.
2/5 = 18/45
4/9 = 20/45
Since 20/45 is bigger than 18/45, we know that 4/9 is greater than 2/5
I'll do the first 2 and 6, and I challenge you to do the other three on your own!
For 1, from some guess and check we can figure out that 5*5=25. Since 5 is a prime number, that's it!
For 2, we can figure out that 7*7=49 and 7 is a prime number, so we're good there.
From 6, we can do some guess and check to figure out that 2*24=48, 2*12=24, 2*6=12, and 2*3=6, resulting in 2*2*2*2*3=48 since 2 and 3 are prime numbers. We found out, for example, to find 2*12 due to that if 2*24=48, 2*24 is our current factorization. By finding 2*12=24, we can switch it to 2*2*12