If the vertices of a triangle are (1, k), (4, -3), (-9, 7) and its area is 15 sq units, find the value(s) of k..                                                                                                                                                      [Ans: -3 ,21/13 ]

Ans:    A(1, k)             B(4, -3)            C(-9, 7)

Area of Δ ABC =1/2 [x₁(y₂ -y₁ )+x₂ (y₃ -y₁ ) + x₁ (y₁ -y₂ )]

= 1/2 [1(-3-7)+4(7-k)+(-9)(k+3)] = 15

-10 + 28 - 4k - 9k - 27 = 30

- 9 - 13k = 30            ⇒        k = -3

| -9 - 13k | = 30

9 + 13k = 30

k = 21/13

k = -3, 21/13

 

 

Posted Date: 4/10/2013 2:33:17 AM | Location : United States

Ask an Expert

Related Discussions:- Find the values of k, Assignment Help, Ask Question on Find the values of k, Get Answer, Expert's Help, Find the values of k Discussions

Write discussion on Find the values of k
Your posts are moderated

Write your message here..

Related Questions

Algebra2;, log6 X + log6 (x-5) = 1 log6 X + log6 (x-5) = 1

Definition of a function, Definition of a Function Now we need to move... Definition of a Function Now we need to move into the second topic of this chapter.  Before we do that however we must look a quick definition taken care of.

What is a negative number, Q. What is a Negative Number? Ans. Neg... Q. What is a Negative Number? Ans. Negative numbers  are very important in mathematics. We say that positive and negative numbers are  opposites  of one another. Here

Determines the angles of depression, A pilot is flying over a straight leng... A pilot is flying over a straight length of road. He determines the angles of depression of two mileposts, 5 miles apart, to be 32° and 48°. a) Find the distance of the plane f

Rounding, i need somehelp i am not the sharpest in the pack so plz help me ... i need somehelp i am not the sharpest in the pack so plz help me thank you i hope you do

Probability rules, Probability Rules A probability is a number as... Probability Rules A probability is a number assigned to the occurrence of an event in a sample space. Probability measures must satisfy three rules. If A is an even

Example of inflection point - set theory and calculus, Need help, Determine... Need help, Determine the points of inflection on the curve of the function y = x 3

Inequalities and intervals, What inequalities and intervals are? If it is g... What inequalities and intervals are? If it is given that a real number 'p' is not less than another real number 'q', we understand that either p should be equal to q or

Integrals involving quadratics - integration techniques, Integrals Involvin... Integrals Involving Quadratics To this point we have seen quite some integrals which involve quadratics.  Example of Integrals Involving Quadratics is as follow: ∫ (x / x 2

Write down those features of such interactions, After seeing some children ... After seeing some children interacting naturally, write down those features of such interactions that make peer learning potentially a better way of learning. Another point that