Question

Find the solution set of the quadratic equation over the set of complex numbers.

Answer 1

Hello :
5x²+12x+8 =0 
delta = 12²-4(5)(8) = -16 =  16i²......(i² = 1)
delta = (4i)²
x1 = (-12+4i)/2          x2 = (-12-4i)/2 
x1 =-6+2i         x2 = -6-2i

Answer 2

Step 1: Multiply 5x2 = 10 so the equation after the first step should look like this 10 + 12x + 8 = 0.

Step 2: Subtract 10 from the 8 and the number by itself cause whatever you do to one side you must do to the other. so the equation should look like this after the second step 12x + -2 = 0 because we subtracted the 10 and the 8.

Step 3: Now we must add the 2 to both sides because we have to do the inverse operation in this problem so once we've done this it should end up looking like this after the 3rd step 12x = 2 because the 2 was a negative.

Step 4: the final step we must divide since an anytime we have a number next to a variable it means multiply but since were using order of operations we have to do the opposite/inverse operation in this problem and we would divide 12 by 2 and get our final answer as x = -6 because the 12 would cancel itself out leaving us with 2 divided by 12 which is 0.16 or -6 depending on if you want it simplified or not the simplified answer would be 0.16 and the non simplified version would be -6