If the complex number x = 3 + bi and |x|2 = 13, which is the value of b?

b = 2

Step-by-step explanation:

We know that |x|² = 13 and x = 3+bi:

(3+bi)² = 13

3² + b² = 13

9 + b² = 13

Subtract 9 from each side:

9 + b² - 9 = 13 - 9

b² = 4

Take the square root of each side:

√b² = √4

b = 2

constant acceleration- a

constant velocity- c

no velocity or acceleration- b

explanation:

for body moving with a constant acceleration, the rate of change of displacement changes over time. this is proven by the increasing gradient of the curve (a) against time.

a body that is moving at constant velocity covers equal distances over equal periods of time, thus the straight line with a constant gradient c.

a stationary body   covers no displacement as time elapses. thus the flat line with   zero gradient.

-14

step-by-step explanation:

2x2 – 2(x+4)

=2x2-2（5+4）

=4-2×9

=4-18

=-14