Question

How do you do this please help me

Answer 1

Perimeter is the sum of the sides.
4x + 6 +3x + 2 = 57
7x + 8 = 57
7x = 49
x = 7

Answer 2

The perimeter of a triangle is the sum of all sides' lengths.

Thus,

$P=6+4x+(3x+2)=7x+8.$

Given $P=57\ cm,$ you get

$7x+8=57,\\ \\7x=57-8,\\ \\7x=49,\\ \\x=\dfrac{49}{7},\\ \\x=7\ cm.$

Answer: x=7 cm.