Answer:
value of x = 2.8
Step-by-step explanation:
By law of cosines,
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
Formula for volume of sphere V = 4/3 (Pi) r^3, where Pi ~ 3.14 and r is the radius = 7.
Therefore V = 4/3 * 3.14 * 7^3
= 4/3 * 3.14 * 343
= 4/3 * 1077.02
= 1,436.02667 cubic units
Answer:
x = 20
Step-by-step explanation:
→ Remember how many degrees are on a straight line
180°
→ Set up an equation
2x + 70 + 3x + 10 = 180
→ Simplify
5x + 80 = 180
→ Minus 80 from both sides
5x = 100
→ Divide both sides by 5
x = 20
Answer:
8 square units
Step-by-step explanation:
The figure is a trapezoid. The area of it is given by the formula ...
A = (1/2)(b1 +b2)h
where b1 and b2 are the lengths of the parallel bases and h is the distance between them.
Your figure shows the base lengths to be 5 and 3, and their separation to be 2. Filling the numbers in the formula, we have ...
A = (1/2)(5 +3)(2) = (1/2)(8)(2) = 4·2 = 8
The area of the figure is 8 square units.
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The right-pointing arrows on the horizontal lines identify those lines as being parallel. The right-angle indicator and the 2 next to the dotted line indicate the perpendicular distance between the parallel lines is 2 units.
