Question

Show how to evaluate the equation for x=2 and x=5 without simplifying first plug in the x values

Answer 1

To evaluate an expression for specific values of \( x \) without simplifying first, you can substitute the values directly into the expression.

Let's say we have an arbitrary equation (for demonstration), such as:

\[
y = 3x^2 + 4x - 5
\]

### Evaluating for \( x = 2 \):

1. Substitute \( x = 2 \) into the equation:

\[
y = 3(2)^2 + 4(2) - 5
\]

This means we directly plug in \( 2 \) for \( x \).

### Evaluating for \( x = 5 \):

2. Substitute \( x = 5 \) into the equation:

\[
y = 3(5)^2 + 4(5) - 5
\]

Now we'll compute the result for both values but we'll follow through without simplifying the whole expression at once.

### Final calculations:

#### For \( x = 2 \):
\[
y = 3(2)^2 + 4(2) - 5 \\
= 3(4) + 4(2) - 5 \\
= 12 + 8 - 5 \\
= 20 - 5 \\
= 15
\]

Thus, when \( x = 2 \), \( y = 15 \).

#### For \( x = 5 \):
\[
y = 3(5)^2 + 4(5) - 5 \\
= 3(25) + 4(5) - 5 \\
= 75 + 20 - 5 \\
= 95 - 5 \\
= 90
\]

Thus, when \( x = 5 \), \( y = 90 \).

### Summary of Results:
- For \( x = 2 \), \( y = 15 \)
- For \( x = 5 \), \( y = 90 \)

This method allows you to see the steps of evaluation without first simplifying the whole equation into a single numeric expression.