- 7z² + 4
distribute the brackets and collect like terms, noting that the second bracket is multiplied by - 1
(2z² + 13 ) - 1(9z² + 9 )
= 2z² + 13 - 9z² - 9 = (2z² - 9z²) + 13 - 9 = - 7z² + 4
Answer:
[tex]\large\boxed{-7x^2+4}[/tex]
Step-by-step explanation:
[tex](2x^2+13)-(9x^2+9)=2x^2+13-9x^2-9\\\\\text{combine like terms}\\\\=(2x^2-9x^2)+(13-9)=-7x^2+4[/tex]
