Hello!
I believe that 8 cubes are needed to build the given figure
I hope this helps!
For number 12 the answer is 15.36
The answer to your question is yes
Answer:
x³ - 5x² + 81x - 405 = 0
Step-by-step explanation:
Complex roots occur in conjugate pairs.
Thus given x = - 9i is a root then x = 9i is also a root
The factors are then (x - 5), (x - 9i) and (x + 9i)
The polynomial is the the product of the roots, that is
f(x) = (x - 5)(x - 9i)(x + 9i) ← expand the complex factors
= (x - 5)(x² - 81i²) → note i² = - 1
= (x - 5)(x² + 81) ← distribute
= x³ + 81x - 5x² - 405, thus
x³ - 5x² + 81x - 405 = 0 ← is the polynomial equation
IN A triangle, sum of all angles = 180 degrees
2x + 3 + 4x+2 + 2x -1 = 180
8x +4 = 180
8x = 176
x = 176 /8 = 22 degrees
the angles are A = 2(22)+3 = 44+3 = 47 DEGREES
B = 4(22)+2 = 88 + 2 = 90 DEGREES
C = 2(22) -1 44-1 = 43 DEGREES