I needs help again but i also mark brainliest if ppl answer

Use set buikder notation to represent the following set: {, -2, -1, 0}

Given abcd ac=38 and ae=3x+4 find the value of x

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.