Answer:
1. 81
2. 108 1/2
3. 189 1/2
Step-by-step explanation:
Step-by-step explanation:

Answer:
5 hours
Step-by-step explanation:
Mark recieves 3mg per hour. This can be rewritten as y=3x. Cassie recieves 2x+5. To solve, use substitiution. 3x=2x+5. To solve, subtract "2x" from "3x." You then get x=5.
Answer:
B
Step-by-step explanation:
6.4 × 1000000 is 6,400,000
10⁶ = 1000000
Half the x-coefficient is -3, so the equation needs to be rearranged into a form that looks like
x² -6x +(-3)² + [something]
You can get there by adding and subtracting 9 from the original equation.
y = x² -6x +9 +7 -9 . . . . . 9 added and subtracted
y = (x² -6x +9) -2
The quantity in parentheses is a perfect square, so we can write the equation in the desired form as ...
y = (x -3)² -2