00:01
Hello students we are given a question here that there is a demand function and supply function we need to find the equilibrium quantity and price okay so we are supposed to know that here for equilibrium for the equilibrium condition okay demand have to be equal to supply so we can write here that the demand have to be equal to supply so we can just say the demand is minus 2 q square minus 2 q square plus 10 q plus 15 ,400 is equal to supply is given as q square plus 20 cube so here we can just say that it should be like a minus 2 q square minus q square it means minus 3 q square okay 10 q minus 20 q it means minus 10 cube and plus 15 000 400 is equals to 0 so basically we can say that it should be 3 q square plus 10 q 3 sorry here we can write that the 3 q square plus 10 q students minus 15 ,400 is equal to 0 now here we are supposed to know that how we will solve it cq is equals to it should be a it is a quadratic equation so we can apply quadratic formula minus b plus minus under root b square minus 4a c divided by 2a so basically minus 10 plus minus under under root of here we can write 10 square students minus 4 times 3 times minus 15 ,400 okay and then divided by 2a so 2 times of 3 students so further we can say that q is equals to minus 10 plus minus under root of 10 square is 100 okay minus minus minus plus here 4 312 times 15 ,400 so what we will get it will be equal to 1 ,084 ,800.
02:04
Okay, students, and then divided by 2306, q is equals to minus 10 plus minus under root of 1 ,084 ,900 and then divided by 6.
02:16
So basically we can say that q is equals to minus 10 plus minus.
02:21
See here under root of 1 ,084 ,900.
02:25
What we will get, it is the square of 430 ,000.
02:29
So we can say that 430 and divided by 6.
02:33
So we will take only positive value.
02:36
So minus 10 plus 430 divided by 6 because the negative value can't be considered because it can't be acceptable as quantity can't be negative...