Question

Given f (x)=-12, find xwhen f (x)=20

Answer 1

Answer:

Step-by-step explanation:How do we set about finding the points in which two graphs y = f(x) and y = g(x) intersect?

We already know how to find where the graph of f(x) cuts the x−axis. That’s where y = 0. We calculate it by solving the equation  f(x) = 0 .

When the graphs of y = f(x) and  y = g(x)  intersect , both graphs have exactly the same x and y values. So we can find the point or points of intersection by solving the equation  f(x) = g(x). The solution of this equation will give us the x value(s) of the point(s) of intersection. We can then find the y value by putting the value for x that we have found into one of the original equations. That is by calculating either f(x) or g(x).

Example 1

Calculate the point of intersection of the two lines f(x) = 2x − 1 and g(x) = x + 1.  First let’s look at a graph of the two functions. We can see the point of intersection is (2, 3).

Answer 2

Answer: f=32

Step-by-step explanation:

_12 +32 =20