Answer:
6x+3 ft
x=7
Explanation:
The perimeter of the triangle is the sum of all 3 sides
x+4 + 3x-2 + 2x+1
Combine like terms
x+3x+2x + 4-2+1
6x +3
The perimeter is equal to 6x+3 ft
We know the perimeter is equal to 45
45 = 6x+3
Subtract 3 from each side
45-3 = 6x+3-3
42 = 6x
Divide by 6
42/6 = 6x/6
7 =x