Answer:
[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{10 {x}^{2} + 2x - 9}}}}}[/tex]
Step-by-step explanation:
[tex] \sf{3 {x}^{2} + 2x - 5 + ( - 4 + 7 {x}^{2} )}[/tex]
When there is a ( + ) in front of an expression in parentheses, there is no need to change the sign of each term.
That means , the expression remains the same.
⇒[tex] \sf{3 {x}^{2} + 2x - 5 - 4 + 7 {x}^{2} }[/tex]
Collect like terms
⇒[tex] \sf{ {10x}^{2} + 2x - 5 - 4}[/tex]
Calculate
⇒[tex] \sf{10 {x}^{2} + 2x - 9}[/tex]
Hope I helped!
Best regards!!
