In both cases you may well benefit from graphing the functions.
Do you recognize f(x) = (x + 1)^2 - 1 as a quadratic function, whose graph is that of a parabola that opens up? By comparing this to y = a(x-h)^2 + k, we see that a=1, h= -1 and k = -1. The vertex is at (h,k), which here is the point (-1, -1). This is the minimum value of the function. Thus, the range of this function is [-1, infinity).
Now for the function f(x) = 7x - 11: This is a linear function whose graph is (surprise!) a straight line. When x increases, y increases, without limits to either. Similarly, when x decreases, y decreases.
Thus the range includes all real numbers: (-infinity, infinity).
We have a right triangle with a 15m hypotenuse and a 8m leg. If we use x for the missing leg then the Pythagorean Theorem states that:

Then we have to solve that equation for x:
![\begin{gathered} x^2=15^2-8^2=225-64 \\ x^2=161 \\ x=\sqrt[]{161} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20x%5E2%3D15%5E2-8%5E2%3D225-64%20%5C%5C%20x%5E2%3D161%20%5C%5C%20x%3D%5Csqrt%5B%5D%7B161%7D%20%5Cend%7Bgathered%7D)
So the answer is the square root of 161.
Same case as Pablo's, more or less.
a = price for the desktop
b = price for the laptop
we know the laptop is 150 bucks more than the desktop,
b = a + 150.
how much is 7% of a? (7/100) * a, 0.07a.
how much is 9.5% of b? (9.5/100) * b, 0.095b.
total interests for the financing add up to 303,
0.07a + 0.095b = 303.

how much was it for the laptop? well b = a + 150.
Given:
The system of inequalities is:


To find:
The graph of the given system of inequalities.
Solution:
We have,


The related equations are:


Table of values for the given equations is:

0 1 -3
3 0 3
Plot (0,1) and (3,0) and connect them by a straight line to get the graph of
.
Similarly, plot (0,-3) and (3,3) and connect them by a straight line to get the graph of
.
The signs of both inequalities are ">". So, the boundary line is a dotted line and the shaded region or each inequality lie above the boundary line.
Therefore, the graph of the given system of inequalities is shown below.
Sarah starts with 3 fish
in 1 month she will have 6 fish
after 2 months she will have 12
in 3 months she will have 24