Q:

The graph shows the functions f(x), p(x), and g(x):Graph of function f of x is y is equal to 4 plus the quantity 1.5 raised to the power of x. The straight line g of x joins ordered pairs 1, 3 and 3, negative 1 and is extended on both sides. The straight line p of x joins the ordered pairs 5, 0 and 6, 3 and is extended on both sides.Courtesy of Texas InstrumentsPart A: What is the solution to the pair of equations represented by p(x) and g(x)? (3 points)Part B: Write any two solutions for g(x). (3 points)Part C: What is the solution to the equation g(x) = f(x)? Justify your answer. (4 points)

Accepted Solution

A:
Part A:
The solution of the equations p(x) and g(x) is the intersection of the two lines.
p(x): y=3x-15..................(1)
g(x): y=-2x+5..................(2)

By comparison, 3x-15=-2x+5 => 5x=20 => x=4 
Substitute x=4 in (1), y=3(4)-15=12-15=-3
=>  Solution: (4,-3)
(see second attached image)

Part B: write any two solutions for g(x).
We cannot write a solution to a function unless there is an equation.
ASSUMING what is meant is to write two points that lie on the line g(x), then we can assume any two values of x, say x1, x2, and evaluate y1=g(x1) and y2=g(x2).
If x1=0, then g(x1)=g(0)=-2(0)+5=5 => point is (0,5)
If x2=1, then g(x2)=g(1)=-2(1)+5=-2+5=3 => point is (1,3) .... and so on.

Part C: what is the solution to the equation g(x)=f(x)
g(x)=f(x) => -2x+5=4+1.5^x => 1.5^x+2x-1=0 .......................(3)
There is no analytic solution to solve this kind of problems.  However, we can always solve it graphically and check the answer algebraically.
As we can see from the third graph, the solution is (0,5).
Check: 1.5^(0)+2(0)-1 = 1+0-1 = 0    => solution (0,5) is good.
Answer: solution is (0,5)