Question

AB=4x
AC=(2x-1)
BC=(5x-2)
luas ABC = 30cm
keliling ???
dgn cara

Answer 1

L = a x t
       2
30 = ac x ab
           2
30 = (2x-1) . 4x
            2
30 = (2x-1) . 2x
30 = 4x² - 2x
4x² - 2x -30 = 0
2x² - x - 15 = 0
(2x+5)(x-3) = 0
x = -5/2
x= 3
x>0 , x = 3
K = AB +AC+BC = 4x + 2x-1 +5x-2 =11x - 3 = 11 . 3 - 3 = 33 - 3 = 30 cm
yeayy.. smoga bantu ya

Answer 2

L = ½ AB. AC 30  = ½ 4x. 2x-1 30 = 2x . 2x-1 0 = 4x2 -2x-30 (x-2,5) (x+3) Kita gunkn x = 2,5 Maka AB = 4x = 4. 2,5 = 10 AC = 2x-1= 2(2,5)-1 = 4 BC = 5x-2 = 5 (2,5) – 2 = 10,5 Jadi keliling = 10+4+10,5 = 24,5