Keep doing each step manually, and see where it slips up:
−7.9+8.2−3.4+2.1=−1
−7.9+8.2+(−3.4)+2.1=−1
−7.9+(−3.4)+8.2+2.1=−1
(−7.9+(−3.4))+(8.2+2.1)=−1
−11.3+10.3=−1
Answer:

Step-by-step explanation:
Combine all the like terms & then solve:


Answer:
x^3-10x^2+x+120
Step-by-step explanation:
Assuming you mean roots -3, 5, 8
These happen when we have (x+3)(x-5)(x-8)=0
Expand this
(x^2-2x-15)(x-8)=0
=x^3-2x^2-15x-8x^2+16x+120
=x^3-10x^2+x+120
Answer:
549 ft
Step-by-step explanation:
take 670ft away from 1,220 ft ( not all the way sure of I'm right)