Answer:
10x³ - 6x² - 9x + 12 is a cubic expression ⇒ 2nd
6x + 6 is a linear expression ⇒ 1st
5x² + 9x - 1 is a quadratic expression ⇒ 2nd
Quadratic expression ⇒ 1st
Step-by-step explanation:
* Lets explain the degree of any expression
- The degree of any expression is the greatest power of the variable
- Ex:
# 3x - 3 is a first degree expression
# x² - 3x + 2 is a second degree expression
# 5x³ - 2x² + 5x - 2 is a third degree expression
- The first degree expression is called linear expression
- The second degree expression is called quadratic expression
- The third degree expression is called cubic expression
* Lets solve the problem
∵ The cubic expression is the expression with greatest power of 3
∴ 10x³ - 6x² - 9x + 12 is the cubic expression
∵ The linear expression is the expression with greatest power of 1
∴ 6x + 6 is a linear expression
∵ The quadratic expression is the expression with greatest power of 2
∴ 5x² + 9x - 1 is a quadratic expression
∵ The expression is -2x² + 11
∵ The greatest power of x is 2
∴ -2x² + 11 is a quadratic expression
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