Answer:
7r³ - 3r² + 20r
Step-by-step explanation:
(9r³ + 5r² + 11r) + (-2r³ + 9r - 8r²)
You can get rid of the parentheses since there is nothing to distribute.
9r³ + 5r² + 11r - 2r³ + 9r - 8r²
Combine like factors.
7r³ - 3r² + 20r
a is given to us so just plug a into the first equation:
b-3 - 3b =9
Add 3 to both sides:
b-3b=12
Combine like terms:
-2b=12
Divide by -2 to get b by itself:
b=-6
The only answer with b as -6 is the first one, (-9,-6)
28 mins = 2 miles
1 min = 2 ÷ 28 = 1/14 miles
70 mins = 1/14 x 70 = 5 miles
Answer: 5 miles
