Answer:
[tex]-2077[/tex]
Step-by-step explanation:
[tex]i=1(-3-4)=-7(first)[/tex]
[tex]i=2(-3-4*2)=-11[/tex]
[tex]i=3(-3-4*3)=-15[/tex]
[tex]i=31(-3-4*31)=-127(last)[/tex]
Difference= -11-(-7)= -4
[tex]sum=\frac{n}{2}[/tex]
[tex]= \frac{31}{2}[-7+(-127)][/tex]
[tex]=\frac{31}{2}*(-134)[/tex]
[tex]=31*(-67)[/tex]
[tex]= -2077[/tex]
✧༝┉˚*❋ ❋ ❋┉༝✧
hope it helps..
have a great day!!
