In a certain triangle, the longest side is twice as long as the shortest side, and the shortest side is 4 inches shorter than the middle side. If the perimeter

Question

A. 10 inches

B. 12 inches

C. 16 inches

D. 20 inches

E. 24 inches

Answer 1

We have 3 unknowns, so we must have 3 equations in order to solve this.

Let x=smallest side

     y=middle length side

     z=longest side

     P=perimeter (note: different value for A, B, C, D and E)

Eq. I: P=x+y+z--->P=x+x+4+2x=4x+4--->(P-4)/4=x

Eq. II: z=2x

Eq. II: x=y-4--->y=x+4

*I will go thru this process for A and you will need to do the same for B, C, D and E.

A. P=10

    Eq.I:  x=(P-4)/4          Eq.II:  z=2x (use value for x from Eq. I)            Eq. III:  y=x+4

             x=(10-4)/4                  z=2(1.5)                                                            y=1.5+4

             x=6/4                         z=3                                                                    y=5.5

             x=1.5

Your answers for A are 1.5, 3 and 5.5.