Answer:
The step 4 is not what he should have done. But the wrong is step 5, because if he added -2x both sides, it would give the following equation:

and not 
Note that in step 4 he should have added 2x and not -2x to both sides, but we still have the equality. The problem is that step 5 is totally wrong.
I don't know what answer is expected to this question, but I would mark step 5, because this is mathematically wrong.
Solving the equation

Using distribution

Add
both sides


Add 12 both sides

Divide both sides by 5

So the diagonal of cube
this was a practice act question so her's the answer
look at the cube through one of the faces
you will see the diagonal as the hypotonuse of a triangle
and also a triangle on the floor (look at attachment)
the ,diagonal is 28
a^2+b^2=28^2
a=b since it is a cube
remember that this is a 45,45 triangle so therefor
a=b=x
c=x√2 so
28=x√2
divide both sides by √2
28/(√2)=x
the diagonal on the floor is 28/(√2)
the sides of the triangle form another 45 45 90 triangle with 28/(√2) as hyponuse so
a=b=x
c=x√2=28/(√2)
solve for x
x√2=28/(√2)
divide both sides by √2
same as mujlitply both sides by 1/(√2) so
28/(√2) times 1/(√2)=28/(2)=14
the answer of 1 diagonal is 14 cm
the answer is 14cm
Answer:
-199
Step-by-step explanation:
- put -6 in place of x in equation
Answer:
Charge Zone
Step-by-step explanation:
If Charge Zone (CZ) costs 15.80 for 20, and Electrocell batteries (EB) costs 8.10 for 10 batteries, you would find the price and quantity amount by multiplying by two. 8.10x2= 16.20, which is more than CZ.
Therefore, CZ is of better value.