Only 1 Can Solve K 5 ² 81 Find K SAT Algebra Challenge SmartMathTricks

Hello viewers welcome to this channel. Today we are going to solve this problem to find k value solution. k plus 5 whole power 2 equal to 81. Here we are going to apply this algebra formula here. So a plus b whole square equal to a square plus 2ab plus b square. This algebra formula we are going to apply here. So we will get here k square here plus 2 times k5 plus 5 square equal to 81. Now k square plus 2 times 5 is 10k plus 5 square is 25 equal to 81. Now k square plus 10k plus 25 moving this h1 left hand side minus h1 equal to 0. Here k square plus 10k here do minus this will get here minus 56 equal to 0. Here this 10k can be written as 10k equal to 14k minus 4k. This we are going to apply here. So k square plus 14k minus 4k minus 56 equal to 0. Here we are going to take this k common out. So k here open bracket we have remaining k here plus 14 close bracket. Here we are going to take minus 4 from this. So minus 4 open bracket k here it is plus this is 14 equal to 0. Now k plus 14 we are going to take common out. k plus 14 here we have remaining k minus 4 equal to 0. Here k plus 14 here k minus 4 equal to 0. From this k plus 14 equal to 0. From here k minus 4 equal to 0. Here k equal to minus 14. Here k equal to 4. This is the possible solution in first method. Now we are going to do this in other method that method 2. The equation here is k plus 5 whole square equal to 81. Here in this method k plus 5 whole square moving this 81 left hand side. So minus 81 equal to 0. So here k plus 5 whole square here this 81 can be written as 9 square equal to 0. Here we are going to apply this algebra formula that a square minus b square equal to a plus b a minus b. This algebra formula we are going to apply it here. So consider this is a this is b. So here k plus 5 plus 9 and k plus 5 minus 9 equal to 0. From this k this is k plus 5 plus 9 equal to 0. From this k plus 5 minus 9 equal to 0. Here k plus this is 14 equal to 0. Here k here it is minus 4 equal to 0. Here k equal to minus 14. Here k equal to 4. This is the possible answer in second method. Now we are going to verify this method. Verify k plus 5 whole square equal to 81. From this method here k equal to minus 14 comma k equal to 4. This we are going to apply here. So minus 14 plus 5 whole square equal to 81. Here this can be written as negative 9 whole square equal to 81. Here negative 9 square is 81 equal to 91. So l s s equal to r s s. Here this is verified. Now we are going to apply this k equal to 4. Here the equation is k plus 5 whole square equal to 81. Here 4 plus 5 whole square equal to 81. Here 4 plus 5 is 9 square equal to 81. Here 9 square is 81 equal to 81. So l s s equal to r s s. Here we have verified. Thanks for watching this video.