Answer:
x= 6 +/- 2i
Explanation:
+/- is the positive or negative symbol
formula: ax^2+bx+c=0
And: X^2-12x+40=0
Then: a= 1 b= -12 c= 1
because none of the greatest common factors will factor into the problem, use the quadratic formula
x= -b +/- sqrt(b^2 -4ac) / 2a
Plug in the numbers
x= -(-12) +/- sqrt[ (-12)^2 -4(1)(40) ] / 2(1)
-(-12)=12
(-12)^2=144
(-4)(1)(40)=-160
x= 12 +/- sqrt(144-160) / 2
-160+144= -16
x= 12 +/- sqrt(-16) / 2
keep in mind
sqrt(-1) = i
i^2 = -1
sqrt(16)=4
so,
x= 12 +/- 4i / 2
Take out the 2’s from numerator (essentially dividing)
x= 2 (6 +/- 2i)
————————-
2
The 2’s in the numerator (outside of the parentheses) and in the denominator cancel each other out
Leaving the answer being
x= 6 +/- 2i