The Domain of an Algebraic Expression - Examples, Exercises and Solutions

Usually we do not know the value of the unknown variable and need to work it out.

However, in this case we know its value and so the first thing we will do is substitute it into the expression—that is, replace each $x$ with the value 0.

5*0-6=
0-6=-6

Therefore, the result is -6.

To answer the question we first need to understand what X is.

X is an unknown, meaning it's a symbol that represents another number, an unknown one, that could be there in its place.

Usually in exercises we'll need to calculate and discover what X is appropriate for each exercise,

but in this case the result is given to us: X=8
Therefore, we can substitute (plug in) the value 8 everywhere X appears in the exercise.

So we get:

5*8-6

40-6
34

The first step is to substitute X in the exercise, resulting in:

$5(-3)-6$

When we have two numbers with different signs, meaning one number is negative and the other is positive or vice versa,

the result of multiplication or division will always be negative.

$5\times-3=-15$

$-15-6=-21$

To solve this problem, we will evaluate the algebraic expression $5x - 6$ by substituting the value of $x = -2$ into it.

Step-by-step solution:

• Step 1: Substitute $x = -2$ into the expression $5x - 6$. This gives:

$5(-2) - 6$

• Step 2: Perform the operations in the expression. Start with the multiplication:

$5(-2) = -10$

• Step 3: Substitute the result of the multiplication back into the expression:

$-10 - 6$

• Step 4: Now perform the subtraction:

$-10 - 6 = -16$

Therefore, the result of the expression when $x = -2$ is $-16$.

Comparing this result with the given choices, we conclude that the correct choice is:

$-16$

Note that we have two unknowns, a and b, and we are also given values for them,

Therefore, let's start by substituting these values in the equation instead of the unknowns:

8*2-1/3*(7+2)=

When there is a number before parentheses, it's like having a multiplication sign between them.

Let's start solving according to the order of operations, beginning with the parentheses:

8*2-1/3*(9)=

Now let's continue with multiplication and division:

16-9/3=
16-3=

‎‎‎‎‎‎‎13

And that's the solution!