Answer:
3: 
4: 
Step-by-step explanation:
Question 3 can be re-written as:

which equals:

Question 4 can be re-written as:

Doing the first 2 brackets gives us:

Expanding these two:

Simplifying it:

Answer:
Step-by-step explanation:
Split it into 2 inequalities:
-8 < y + 2x
y + 2x < 14
Isolate y , subtract 2x from first and then from second
-8 -2x < y
y < 14 -2x
Rewrite it so it looks pretty?
y > -2x-8
y < -2x +14
You can use the calculator to graph each inequality.
The solution or the system is the area where the 2 solutions for each line overlap.
Answer:
$2,416.77
Step-by-step explanation:
The weighted average balance is ...
(3880×4 +2950×12 +1600×15)/(4+12+15) = 74920/31 ≈ 2416.77
The average daily balance is $2,416.77.
Answer:
Equation C. 5.1 + 2y + 1.2 = -2 + 2y + 8.3
Step-by-step explanation:
Equation C is the only equation in the list in which the terms that contain the unknown "y" on each side of the equal sign are identical, therefore when solving for this unknown and trying to group them on one side, they go away, leaving us with a relationship among numerical values that is always true:
5.1 + 2y + 1.2 = -2 + 2y + 8.3
5.1 + 1.2 = -2 + 8.3
6.3 = 6.3
Then this equation is true for any value of the unknown y, and y- can adopt infinite number of values, independent of which the equation will always be a true statement (giving thus infinite number of solutions).