Stephen and aaron solved the same equation using two separate methods. their work is shown in the table below:
stephen aaron:
3x - 2 = 5x - 6 3x - 2 = 5x - 6
3x - 2 + 2 = 5x - 6 + 2 3x - 3x - 2 = 5x - 3x - 6
3x = 5x - 4 -2 = 2x - 6
3x - 5x = 5x - 5x - 4 -2 - 6 = 2x
-2x = -4 -8 = 2x
x = 2 -4 = x
identify who made the error and what he did wrong.
aaron made the error when he subtracted 6.
aaron made the error when he subtracted 3x.
stephen made the error when he added 2.
stephen made the error when he subtracted 5x.

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!

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk