Question

Kak jawab ini dong

pleaseeee

tolong bantuannya ya☺

Answer 1

Verified answer

Jawab

a) luas ABCD = 20 x 12 = 240

b) luas segitiga
Δ SDR = x(20-x)/2 = 10x - 1/2 x²|
Δ RCQ = x(12-x)/2 = 6x - 1/2 x²
Δ BPQ = x (20-x)/2 = 10x - 1/2 x²
Δ APS  = 1x(12-x)/2 = 6 x- 1/2 x²
jumlah luas Δ  = 32 x - 2x²
LuasPQRS = luas persegi - jumlah luas Δ
L(x) = 240- (32x -2x²)
L(x) = 2x² - 32 x + 240
Maksimum jika L '(x) =0
4x -32 = 0
x= 8

L(8) = 2 (8²) - 32(8) + 240
L(8) = 128 - 256 + 240
L(8) = 112