Answer:
=
2
5
Step-by-step explanation:
−
2
0
=
5
n-20=5
n−20=5
−
2
0
+
2
0
=
5
+
2
0
Answer:
Option A is correct
Difference of squares identity should be used to prove 49-4 =45
Step-by-step explanation:
Prove that : 49 - 4 = 45
Polynomial identities are just equations that are true, but identities are particularly useful for showing the relationship between two apparently unrelated expressions.
Difference of the squares identity:

Take LHS
49 - 4
We can write 49 as
and 4 as
.
then;

Now, use the difference of square identity;
here a =7 and b = 2

or
= RHS proved!
therefore, the difference of square polynomial identity should be used to prove that 49-4 =45
Charge of Ralph:
Charge = $24 + $33 per hour
Let the time worked be = x.
For x hours, the cost = 33*x = 33x
Charge = 24 + 33x
24 + 33x = 189
33x = 189 - 24
33x = 165
x = 165/33
x = 5
The job took 5 hours.
I hope this helped