Question

33.

Answer 1

By definition, perpendicular line are two lines that intersect at right angles. In other words, the angle made by two lines should be 90°. Therefore, the use of distance formula does not help because it only tells you if the sides are equal. It does not tell you about the intercepted angle.

A technique that can help you to know if two straight lines are perpendicular is is you find their slopes. Let's say the slope of line 1 is m1 and the slope of line 2 is m2. If m1*m2 yields a product of -1, then the lines are perpendicular. This is because if m1 is the negative reciprocal of m2, the lines are perpendicular. But if m1=m2, the lines are parallel, meaning they don't intersect at all.

Therefore, the answer is: Find the slopes and show that their product is -1.

Answer 2

Answer: The answer is (d) Find the slopes and show that their product is -1.

Step-by-step explanation:  Given in the question and shown in the attached figure that the vertices of the quadrilateral PQRS are P(0, 0), Q(a + c, 0), R(2a + c, b), and S(a, b). We are asked to use geometry to show that the diagonals PR and QS are perpendicular to each other.

We know that the two lines are perpendicular if the product of their slopes is --1.

So, first we will find the slopes of PR and QS, multiply them, and check the value.If the value is -1, then the diagonals are perpendicular to each other.

That is, if 'm' and 'p' are the slopes of the diagonals PR and QS, and if m × p = -1, then the two diagonals are perpendicular.

Thus, the correct answer is (d).