Triangle algebra math problem

Question

The triangle and the square shown have the same perimeter. Solve the equation 3x+4x+5x=4(x+2) to find the value of x. Then find the length of one side of the square. 

 

Answer 1

Original equation 3x+4x+5x=4(x+2)

Step 1 combine like terms = 12x = 4x+8

Step 2 put all the x values together 12x - 4x = 8

Step 3 combine the x terms 8x = 8

Step 4 get x by itself by dividing both sides by 8 8x = 8

8 8

Answer is X=1

Proof: Triangle = 3x+4x+5x = ?

substitute x for 1 = 3(1)+4(1)+5(1) = 12

Proof Square = 4(x+2)

substitute x for 1 = 4(1+2) = 4(3)= 12

Answer:

Length of 1 side of the square = x+2

substitute x for 1 = 1+2 = 3