Question

Question 1 of 5 Which is equivalent to (3t – 9) • (5+3 – 15 42 +19)? A 15t4 – 45+3 + 15t2 + 577 – 171 B 15t4 50+3 + 15t2 + 577 + 171 C 15t4 – 50+3 – 15t2 +57t – 171 D 15t4 50+3 + 15+2 +57t – 171

Answer 1

D

`15t^4-50t^3+15t^2+57t-171`

Step-by-step explanation:

Given the below expression;

`(3t-9)\ast(5t^3-(15)/(9)t^2+19)`

Let's go ahead and clear the brackets by using each of the terms in the first bracket to multiply all of the terms in the 2nd bracket;

`(3t\ast5t^3)-(3t\ast(15)/(9)t^2)+(3t\ast19)-(9\ast5t^3)+(9\ast(15)/(9)t^2)-(19\ast9)`
`\begin{gathered} =15t^4-5t^3+57t-45t^3+15t^2-171 \\ =15t^4-50t^3+15t^2+57t-171 \end{gathered}`