Recent content by purplecows

If I switch 2 rows, do I have to multiple by -1 each time? For example, I have If I switch row 2 and 3, will it become this: Or this? Each time I make a switch, do I have to also put a negative sign? Edit: Not really related to Gaussian elimination, but this is from a Gaussian...

So I fixed that and even then, the answer was still way off. Can someone explain how to do this step by step with the final solution?

Homework Statement Find the points of tangency to a circle given by x^2+y^2=9 from point (12,9). Homework Equations dy/dx=-x/y (what I've been able to come up so far) The Attempt at a Solution Taking the derivative I got dy/dx=-x/y Let the unknown point of tangency be (a,b)...

Homework Statement A 40.0-kg object is being pulled along a horizontal surface by means of a rope that exerts a force of 200 N at an angle of 30° below the horizontal. The coefficient of static friction between the object and the surface is 0.40. The force of friction on the object is: A) 197...

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Homework Statement An object that is moving at a constant speed velocity is acted upon by three forces. One force is 150 N along the x-axis, the second is 100 N along a direction making a counterclockwise angle of 120° with the x-axis. What is the magnitude of the third force? Homework...