Decide whether each of the following is a quadratic equation or not. Write Yes or No in the proper blank.?

Question

a. 3 – X^2 = 9x
b. X^3 – 8 = 0
c. 2X^2 – 7X + 1
d. -5 – X^2 + 8X = 0
e. 6 + 5X – X^2

Answer 1

a. yes
b. no. It is cubic.
c. Not an equation as the "=" sign is not present
d. yes
e. Not an equation as the "=" sign is not present.

Answer 2

quadratic equation has the following form:

aX^2 + bX + c = 0

you can arrange the questions to fit the above form.
a. -X^2 -9X + 3 = 0 yes

try to do the rest
b. no
c. no (there is no equal sign)
d.yes
e.no (there is no equal sign)

Answer 3

a no
b no
c y
d y
e y

Answer 4

Review your definition and solve this yourself.