Help please 3 i'm so confused

The lengths of all sides of a triangle are integers when measured in decimeters. one of the sides has length of 1 dm and another of 3 dm. find the perimeter of the triangle.'

30 ! the graph shows the number of siblings different students have. select from the drop-down menus to correctly complete the statement.

Given: m zade = 60° and m2cdf = (3x + 15) prove: x = 15