Do lulus way. If you change the angles, you will not have a pentagon anymore. If you subtract, it wouldn’t be the same ratio:)
Answer:
x = 1.2375 or 99/90
Step-by-step explanation:
<u>Step 1: Distribute</u>
21 + 40(2x - 3)
21 + 80x - 120
<u>Step 2: Combine like terms</u>
21 + 80x - 120
80x - 99
<u>Step 3: Solve for x</u>
80x - 99 + 99 = 0 + 99
80x / 80 = 99 / 80
x = 1.2375
Answer: x = 1.2375 or 99/80
16.5 mg of calcium per tablet × 20 tablets=
330 mg of calcium
Answer:-2-5÷4-1=-1
Step-by-step explanation:
<span><span> <span>Akar akar persamaan kuadrat 2x² - 3x -1 = 0 adalah x1 dan x2. Persamaan kuadrat baru yang akar akarnya satu lebih kecil dari dua kali akar akar persamaan kuadrat di atas adalah ........</span></span><span><span><span>A.x² - x - 4 = 0</span><span>B.x² + 5x - 4 = 0</span><span>C.x² - x + 4 = 0</span></span><span><span>D.x² + x + 4 = 0</span><span>E.x² - 5x - 4 = 0</span></span></span><span>Jawaban : A
Penyelesaian :
Akar-akar persamaan lama : x1 dan x2
Akar-akar persamaan baru : xA dan xB
xA = 2x1 - 1
xB = 2x2 - 1
xA + xB = (2x1 - 1) + (2x2 - 1)
= 2 (x1 + x2) - 2
= 2 () - 2
= 3 - 2
xA + xB = 1
xA . xB = (2x1 - 1) (2x2 - 1)
= 4 x1.x2 - 2(x1 + x2) + 1
= 4.(-) - 2() + 1
= -2 - 3 + 1
xA . xB = -4
Jadi persamaan kuadrat baru : x² - (xA + xB)x + xA . xB = 0
x² - x - 4 = 0
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