Answer: a. -3(x+1), b. 19-3x, c. -9 and d. 13
Step-by-step explanation:
Lets begin with a. (fog)(x)=f(g(x))
=f(2x+x+7), Note that 2x+x+7=3x+7
=f(3x+7) (where there is x if the function f(x) we
substitute x by 3x+7)
=4-(3x+7) =4-3x-7=-3x-3= -3(x+1).
b. (gof)(x)=g(f(x))=g(4-x) (where there is x in the function
g(x) we substitute with 4-x)
= 3(4-x)+7 = 19-3x
c. (fog)(2) = -3(2+1) = -9 (we now substitute x with 2 in -3(x+1). )
d. (gof)(2) = 19-3(2)=19-6=13. (Again we now substitute x with
2 in 19-3x)
Its 86,563,140 and how do you add a question
Part A: Explain why the x-coordinates of the points where the graphs of
the equations y = 4-x and y = 2x + 3 intersect are the solutions of the
equation
4-x = 2x + 3.
Because the point where the graphs intersect is a point that meets both rules (functions) y = 4 - x and y = 2x + 3 meaning that y from y = 4 - x equals y from 2x + 3 and also both x have the same value.
Part B: Make tables to find the solution to 4-x = 2x + 3. Take the integer values of x between -3 and 3.
x values 4 -x 2x + 3
-3 4-(-3)=7 2(-3)+3 =-3
-2 4-(-2)=6 2(-2)+3 =-1
-1 4-(-1)=5 2(-1)+3 = 1
0 4-0=4 2(0)+3 = 3
1 4-1=3 2(1)+3=5
2 4-2=2 2(2)+3 = 7
3 4-3=1 2(3)+3 = 9
The the solution is between x = 0 and x =1
Part C: How can you solve the equation 4-x = 2x + 3 graphically?
Draw in a same graph both functions y= 4 - x and y = 2x +3.
Then read the x-coordinates of the intersection point. That is the solution.
In order from least to greatest it is: 3/8, 2/3, 3/4. To find this on your own get common denominators and compare. Hope this helps.
When calculated your answer is 162
