If we expand -7x ( 5 - x ) .. .....we have to multiply the outside term with the inside values
there fore if we multiply 7 and 5 the answer is 35....... and the negative symbol will make it negative so it will be -35 and the x in the outside value will be multiplied to it so it will become -35x.....
then if we multiply -7x and -x ...... - sign and the other - sign when multiplied will make + sign and when x and x are multiplied from both sides it comes as x^2 ( this means x squared )........when 7 is multiplied the final answer will be 7x^2.......
so we will have -35x + 7x^2 SO when this will be arranged in descending order it means from biggest to smallest....so this will be 7x^2 - 35 x
