Question

10. What makes an equation a quadratic?

A. The equation has a variable multiplied by itself 3 times. A cubed variable.
B. The equation has a variable by itself. x raised to the first power.
C. The equation has a variable multiplied by a number. For example 3x
D. The equation has a variable multiplied by itself. A squared variable.

Answer 1

D. The equation has a variable multiplied by itself. A squared variable.

Explanation:

Yes, they are different. Imagine your random variable takes only the values 0 and 1, with equal probability.

Squaring your value gives 0 and 1 with equal probability;

multiplying by itself gives 0*0,0*1,1*0, and 1*1 with equal probability.

The first has an expected value of .5 the second 0.25

Answer 2

D. The equation has a variable multiplied by itself. A squared variable.

Explanation:

A quadratic equation will always start with a term being squared. For example,
`8x^(2)` + 5x + 7 = 44. Another example would be
`4x^(2)` + 2x - 10 = 12. These are just random numbers, but the equation will always look the same! Hope this helps!