Answer:
15.5 ft
Step-by-step explanation:
The geometry of the problem can be modeled by a right triangle with hypotenuse 16 ft and one side length of 4 ft. If x represents the height of the ladder on the building, then the Pythagorean theorem tells us ...
x^2 + (4 ft)^2 = (16 ft)^2
x^2 = 240 ft^2 . . . . . . subtract 16 ft^2
x ≈ 15.5 ft . . . . . . . . . . take the square root
The top of the ladder is about 15.5 ft above the ground.
Well, the interseciton of 2 planes would be a line, so it would be like line AB when it goes through the 2 points A and B
The answer is C.
The definition of a "quadratic equation" is any equation that has a variable with an unknown value to a power no less than or more than 2. A is not the answer because nothing is to the 2nd power. B, although is to the second power, is simplified into just 4, so it has neither an unknown variable nor power of 2. D is also incorrect because when the 3 is distributed, the equation is just simply 12-3x, which has no power of 2. So C is correct because when the 7x is distributed, you get the equation 7x^2 +21x, which has both a variable with an unknown value and a power of two.
