 Hi, and welcome to the session. My name is Shashi and I'm going to help you to solve the following question. Question is, form the pair of linear equations for the following problems and find their solution by substitution method. Second part is, the larger of two supplementary angles exceeds the smaller by 18 degrees. Find them. First of all, we should understand that the sum of supplementary angles is 180 degrees. This is the key idea to solve this question. Let us start with the solution now. Let the larger of the two angles be equal to x degrees and the smaller angle equal to y degrees. Now, according to the question, angles are supplementary. So, their sum must be equal to 180 degrees. Condition given to us in the question is that the larger of the two supplementary angles exceeds the smaller by 18 degrees. This implies the difference between the two angles is equal to 18 degrees. So, we can write x minus y is equal to 18 degrees, right? Let us now name these equations as equation number 1 and equation number 2. Now, from equation 2, we get the value of x is equal to 18 plus y. Now, let us name this equation as 3. Now, substituting the value of 3 in 1, we get, substituting the value of x, we get 18 plus y plus y is equal to 180 degrees. This implies 18 plus 2y is equal to 180 degrees. This implies 2y is equal to 180 minus 18 degrees. This implies 2y is equal to 162 degrees. This further implies y is equal to 162 upon equal to 81 degrees. So, therefore, y is equal to 81 degrees. Substituting the value of y in equation 3, we get x is equal to 81 plus 18 or we can say x is equal to 99 degrees. Two angles are 99 degrees and 81 degrees. So, pair of linear equations is x plus y is equal to 180 degrees and x minus y is equal to 18 degrees and the two angles are x is equal to 99 degrees and y is equal to 81 degrees. This completes the session. Hope you enjoyed the session. Goodbye.