Help me with number 15, will give brainliest:)

△cde maps to △stu with the transformations (x, y) arrowright (x − 2, y − 2) arrowright (3x, 3y) arrowright (x, −y). if cd = a + 1, de = 2a − 1, st = 2b + 3 and tu = b + 6, find the values of a and b. the value of a is and the value of b is .

Is it true or false i’m trying to pass this test so i can leave school

Math it's appreciated. (picture provided)