Tolong jawab yaa penting bgtt 1-3

3x° + ( x-10)° + (2x + 10)° = 180°
3x° + x° - 10° + 2x° + 10° = 180°
6x° = 180°
x° = 180/6
x° = 30°

a + a + (a-5) = 25
a + a + a - 5 = 25
3a - 5 = 25
3a = 25 + 5
3a = 30
a = 10
maka alasnya = 10 - 5= 5cm
kedua sisi yang sama panjang/kaki segitiga masing masing= 10cm

(3x + 5) - 2(x-1)
= 3x + 5 -2x + 2
= x + 7

L = p.l
L = (x+7) (x-1)
L = x² + 6x - 7

semoga membantu