Amath class is having a discussion on how to determine if the expressions 4x-x+5 and 8-3x-3 are equivalent using substitution. the class has suggested four different methods. which describes the correct method? a. both expressions should be evaluated with one value. if the final values of the expressions are both positive, then the two expressions must be equivalent. b. both expressions should be evaluated with one value. if the final values of the expressions are the same, then the two expressions must be equivalent. c. both expressions should be evaluated with two different values. if for each substituted value, the final values of the expressions are positive, then the two expressions must be equivalent. d. both expressions should be evaluated with two different values. if for each substituted value, the final values of the expressions are the same, then the two expressions must be equivalent.

option (b) is correct.

Both expressions should be evaluated with one value. If the final values of the expressions are the same, then the two expressions must be equivalent.

Step-by-step explanation:

Given : A math class is having a discussion on how to determine if the expressions 4x - x + 5 and 8 - 3x - 3 are equivalent using substitution.

We have to choose the correct method from the given options that the class has suggested.

Since we have to show the given expressions 4x - x + 5 and 8 - 3x - 3 are equivalent using substitution.

We will choose a single value of x  and then evaluate both the  given expression at that single value and if the output of both expression comes out to be same then the two expressions must be equivalent.

For example lets take x = 2,

Then  expression 4x - x + 5 becomes 4(2) - 2 +5 = 8 - 2 + 5 = 6 + 5 = 11

also, expression 8 - 3x - 3  becomes 8 - 3(2) - 3 = 8- 6 - 3 = 8  - 9  = -1

thus, the value is not equal hence, the two expression are not equivalent.

Thus, option (b) is correct.

Both expressions should be evaluated with one value. If the final values of the expressions are the same, then the two expressions must be equivalent.

£56

step-by-step explanation:

let's add {f(x)=x+1}f(x)=x+1 and {g(x)=2x}g(x)=2x together to make a new function.

f(x)+g(x) =(x+1)+(2x)=x+1+2x=3x+1

let's call this new function hh. so we have:

{h(x)}={f(x)}+{g(x)}{=3x+1}h(x)=f(x)+g(x)=3x+1

we can also evaluate combined functions for particular inputs. let's evaluate function hh above for x=2x=2. below are two ways of doing this.

method 1: substitute x=2x=2 into the combined function hh.

h(x)

h(2)

​    

=3x+1

=3(2)+1

=7

​ since h(x)=f(x)+g(x)h(x)=f(x)+g(x), we can also find h(2)h(2) by finding f(2) +g(2)f(2)+g(2).

first, let's find f(2)f(2):

f(x)

f(2)

​    

=x+1

=2+1

=3

​  

now, let's find g(2)g(2):

g(x)

g(2)

​    

=2x

=2⋅2

=4

​  

so f(2)+g(2)=3+4=\greend7f(2)+g(2)=3+4=7.

notice that substituting x =2x=2 directly into function hh and finding f(2) + g(2)f(2)+g(2) gave us the same answer!