∆ABC is an isosceles triangle. The length of CB is 12 feet 4 inches and the congruent sides are each 3/4 this length. 2. What is the perimeter of ∆ABC?a. 31 ft. 4 in.b. 21 ft. 7 in.c. 30 ft. 10 in.d. 18 ft. 6 in.3. In ∆DEF, DE and DF are each 6 feet 3 inches long. This length is 0.75 times the length of FE. What is the perimeter of ∆DEF?a. 12 ft. 4 in.b. 17 ft. 2 in.c. 14 ft. 7 in.d. 20 ft. 10 in.4. ∆JKL is an isosceles triangle with JL ≅ KL. If JK is three more than x, KL is 17 less than four times x, and JL is 45 less than six times x, find x and the measure of each side.e. 39, 39, 17f. 17, 15, 17g. 17,17,39h. 42,42,42​

Answer:Answer for 2nd is option c, for 3rd is option d, for 4th is option eStep-by-step explanation:As we know 1 ft.=12 in.In ΔABC    ∴ The congruent sides are AB and AC respectivelyCB =12 ft. 4 in.=148 in.AB=[tex]\frac{3}{4}[/tex]CB =111 in. =9 ft. 3 in.AC=[tex]\frac{3}{4}[/tex]CB =111 in. =9 ft. 3 in.     ∵  Perimeter of ΔABC =AB+AC+CB                                         =9 ft. 3 in. + 9 ft. 3 in. +12 ft. 4 in.                                         =30 ft. 10 in.     2. In ΔDEF     ∴ The congruent sides are DE and DF respectivelyDE =  6 ft. 3 in. =75 in.DF =  6 ft. 3 in. =75 in.Let the length of FE is equal to x0.75FE =DE =DF0.75x = 6 ft. 3 in. =75 in.x =100 in. =8 ft. 4 in.    ∵ Perimeter of ΔDEF =DE+DF+FE                                         = 6 ft. 3 in. +6 ft. 3 in. +8 ft. 4 in.                                         = 20 ft. 10 in.     3. In ΔJKL     ∴ The congruent sides are JL and KL respectively JK = x+3 KL =4x-17 JL  =6x-45JL≅KL4x-17 =6x-45  . . . . . . . . . . . . . . . . . . . . . . . (1)Subracting 4x from both sides from eq 1-17 =2x-45Adding 45 on both the sides 28 =2xDividing by 2 on both sides14 =xJK = 14+3 =17KL = 4×14-17 =39JL = 6×14-45 =39    ∵ The dimensions of the ΔJKL are 39,39 and 17.