What is the degree of the polynomial 2st4 + s2t2 - 9s5t + 21 ?

Question

What is the degree of the polynomial 2st4 + s2t2 - 9s5t + 21 ?
Choose one answer.

A. 2
 

B. 4
 

C. 6
 

D. 21

Answer 1

May, I hope I can still help.

 

Normally, the degree is the highest exponent in the expression.  The degree of x⁵ - x³ - 2 is 5.

 

However, when we have more than one variable, we add the degrees of the variables in each term to get the degree of each term.  

 

The degree of x⁵y² is 7.  Remember that the degree of x is 1.

 

Let's add what we have. 2st⁴ - 1 + 4 = 5.

 

s²t² - 2 + 2 = 4

 

9s⁵t - 5 + 1 = 6

 

21 - degree of 0 (remember also that anything to the 0 power is 1, so we technically have 21x⁰ = 21(1) = 21).

 

Which is the highest total?  Our degree is 6, so the answer is C.

 

Hope this helps!