Questions on picture. Please help

d. 14 - 12i

Step-by-step explanation:

To find the conjugate of a complex number, you just need to swap the sign in front of the imaginary number (_i)

another example

Conjugate of -3 + 7i would be -3 - 7i

-7/8

step-by-step explanation:

instead of subtracting you add the -6/8 and -1/8

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15