Answer:
12
Step-by-step explanation:
Answer:
A
Step-by-step explanation:
Since the triangle is right use Pythagoras' identity to find EF
The square on the hypotenuse is equal to the sum of the squares on the other two sides, that is
EF² + DF² = DE² ← substitute values
EF² + 12² = 18², that is
EF² + 144 = 324 ( subtract 144 from both sides )
EF² = 180 ( take the square root of both sides )
EF = 
→ A
Answer:
Option B
Step-by-step explanation:
Complex roots occur as conjugate pairs so the third root is -3 - i ( note that the sign changes from + to -).
So in factor form we have:-
(x - 2)(x - (-3 + i))(x - (-3 - i)) = 0 Let's expand the last 2 factors first:-
(x - (-3 + i))(x - (-3 - i))
= (x + 3 - i)(x + 3 + i)
= x^2 + 3x +ix + 3x + 9 + 3i - ix - 3i - i^2
= x^2 + 6x + 9 - (-1)
= x^2 + 6x + 10
Now multiplying by (x - 2):-
(x - 2)(x^2 + 6x + 10) = 0
x^3 + 6x^2 + 10x - 2x^2 - 12x - 20 = 0
x^3 + 4x^2 - 2x - 20 = 0 (answer)
Option B
Answer:
12.5%
Step-by-step explanation:
big brain
answer - true
all rectangles have four sides, and a shape is a quadrilateral if it has four sides
therefore, all rectangles are quadrilaterals
