Answer:
a. X= 0
b. X= undefined or X=4i
c. X= + or - 7
Step-by-step explanation:
a. x² + 4 = 4
when 4 goes to the other side by negative sign it will cancel the other 4. at they equal in magnitude and opposite in sign.
then x² = 0 , where √x²=√0 , finally x=0
b. x² + 16 = 0
16 goes to other side by negative sign too
x² = -16 , where √x²=√-16 , finally x= undefined
due to the negative sign under thr square root.
at √-1 = i then x can be 4i
c. x² - 49 = 0
-49 go to the other side by positive sign
x² = 49 , where √x² = √49 , finally x= + or - 7
where negative sign is neglected at even power
example:
(-7)²=(7)²
