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Example1

Title: The Identity property

Grade 6+ Lesson s2-l5

Explanation: The best way to understand algebra is by looking at some examples. Take turns and read each example for easy understanding.

Examples

Topics → Definition Example1

Evaluate the expression when \$-5x^2 + 3x + 7\$ when x = -2.

Step 1

Given expression \$-5x^2 + 3"x" + 7\$

Substitute the given x = -2 in the given equation

\$- 5(- 2)^2 + 3(- 2) + 7\$

Explanation:

Here, substitute the variable value in the expression.

Step 2

Now, perform the calculation

-5(4) - 6 + 7

-20 - 6 + 7

-26 + 7

-19

The value of the evaluated expression is - 19.

Explanation:

Therefore, when x = −2, the value of the expression \$−5"x"^2 + 3"x" + 7\$ is − 19.