Maths Questions

1.
Let x be the height of building
thus, the shadow is 4x long
tan (angle of elevation) = x / 4x = 1/4
angle of elevation = ...

2. (remember equation as a form of y = mx + c => m is slope and c is y-int)
4x + 5y - 6 = 0
5y = -4x + 6
y = (-4/5)x + (6/5)
a.
the slope of the equation is -4/5
b.
the y-int is 6/5

3. (impossible to solve two variables (x, K) with only one conditions)
x = 1, K = -5
x = 2, K = -17/2
....