The first side of a triangle is 3 m shorter than the second side. the third side is 4 times as long as the first side. the perimeter is 27 m. find the width and length. can you me answer this ?

Me solve this problem, and someone clearly explain to me how to solve it.1.) use the value of the discriminant to determine if the given trinomials has 2 real solutions, 1 real solution, or no real solutions.a.  x2  − 4x  − 7 = 0b. 4r2  + 11r  − 3 = 0c. 3m2  + 7 = 0d.  t2  + 2t  + 1 = 0