Remark
There is no short way to do this problem and no obvious way to get the answer other that to solve each part.
Solve
A
Multiply by 2
x + 1.6 = 2(x + 0.1) Remove the brackets
x + 1.6 = 2x + 0.1*2
x + 1.6 = 2x + 0.2 Subtract x from both sides
1.6 = x + 0.2 Subtract 0.2 from both sides
1.6 - 0.2 = x
1.4 = x
Circle A
B
Subtract 2x from both sides.
3x - 2x = 1.4
Circle B
C
Remove the brackets.
4x + 6 = 2x - 6 Add 6 to both sides
4x + 12 = 2x Subtract 4x from both sides.
12 = -2x Divide by - 2
12/-2 = x
x = - 6 Don't circle C
D
I'm going to be very scant in my solution of this. You can fill in the steps.
3x = 4.2
x = 4.2/3
x = 1.4
Circle D
Answer: 
Step-by-step explanation:
Let be "C" the circumference of the circle (in feet) and "r" the radius of the circle (in feet).
Based on the information provided in the problem, you know that the circumference of the circle is always 
as large as its radius.
Notice that this indicates a multiplication. Then, this means that the circumference of the circle is always equal to by "r".
Based on this, you can write the following formula that expresses the circumference "C" in terms of the radius "r":
Answer:
Step-by-step explanation:
The graph you see there is called a parabola. The general equation for the graph is as below
To find the equation we need to find the constants a and b. The constant b is just how much we're lifting the parabola by. Notice it's lifted by 1 on the y axis.
To find a it's a little more tricky. Let's use the graph to find a value for a by plugging in values we know. We know that b is 1 from the previous step, and we know that when x=1, y=3. Let's use that!
Awesome, we've found both values. And we can write the result.
I'll include a plotted graph with our equation just so you can verify it is indeed the same.
