the variables x, y, and z represent polynomials where x = a, y = 3a - 5, and z = a² + 2. what is x²y - z in…

the variables x, y, and z represent polynomials where x = a, y = 3a - 5, and z = a² + 2. what is x²y - z in simplest form?\n2a² - 5a - 2\n3a³ - 6a² - 2\n-3a³ - 2\n-3a² - 2
Answer
Answer:
B. $3a^{3}-5a^{2}-2$
Explanation:
Step1: Calculate $X^{2}$
Since $X = a$, then $X^{2}=a\times a=a^{2}$.
Step2: Calculate $X^{2}Y$
$X^{2}Y=a^{2}(3a - 5)=3a^{3}-5a^{2}$ (using distributive property $m(n - p)=mn-mp$, here $m = a^{2}$, $n = 3a$, $p = 5$).
Step3: Calculate $X^{2}Y - Z$
$X^{2}Y - Z=(3a^{3}-5a^{2})-(a^{2}+2)=3a^{3}-5a^{2}-a^{2}-2=3a^{3}-6a^{2}-2$.