103,791 views
19 votes
19 votes
HELP PLS EXPLAINNN THIS TO MEEE I DONT UNDERSTAND

HELP PLS EXPLAINNN THIS TO MEEE I DONT UNDERSTAND-example-1
User Kekert
by
3.3k points

1 Answer

21 votes
21 votes

Answer:

The second option is the correct one.

Explanation:

The algebraic expression is as such:


10x^(2)y+6x^(2)-7y^(2)-6

Step 1: Looking at the first element

The first term/element of the final expression is
10x^(2)y.

Only like variables can be added or subtracted from each other (
x can be added to
x to give
2x, but
x added to
y doesn't yield a different result).

In the options, there are two terms which have the variables
x^(2)y:


8x^(2)y and
2x^(2)y.

In the first three options,
8x^(2)y is being added to
2x^(2)y, which would give a result of
10x^(2)y:


8x^(2)y+2x^(2)y\\=(8+2)x^(2)y\\=10x^(2)y

But the fourth option subtracts
2x^(2)y from
8x^(2)y, which wouldn't equal to
10x^(2)y, and so the fourth option isn't correct.

Step 2: Looking at the second element

The second term/element of the final expression is
6x^(2).

In the options, there are two terms which have the variables
x^(2):


7x^(2) and
x^(2).

In the rest of the three options,
x^(2) is being subtracted from
7x^(2), which would give a result of
6x^(2):


7x^(2)-x^(2)\\=(7-1)x^(2)\\=6x^(2)

So, we can't eliminate any options based on this.

Step 3: Looking at the third element:

The same thing as the second element happens with
-7y^(2), so we can't use it either.

Step 4: Looking at the 3x that are being cancelled out

We can see that the options contain the term
3x, even though it is nowhere to be seen in the final expression.

This means that
3x is subtracted from itself to produce a result of
0 (
3x-3x=0), thus it is not present in the final expression.

In the second and third options, we can see that
3x is being subtracted from itself.

But, the first option has
3x being added to itself.
This would produce a result of
6x:


3x+3x\\=(3+3)x\\=6x

Which isn't present in the final expression.

Thus, the first option is also incorrect.

Step 5: Looking at the fourth element

The fourth term/element of the final expression is
-6.

In the options, there are two terms which are also integers:


-2 and
4.

In the second option,
4 is being subtracted from
-2, which would give a result of
-6:


-2-4\\=-6

But in the third option,
4 is being subtracted from
2, which would give a result of
-2 instead of
-6,
So, the third option is also wrong.

User Donald Jansen
by
3.4k points