Question

2x + 3 if x = -2
-4ab if a = 2, and b = -1

Explanation:

For \( 2x + 3 \) when \( x = -2 \):

Step1: Substitute \( x = -2 \)

Substitute \( x = -2 \) into \( 2x + 3 \), we get \( 2\times(-2)+3 \).

Step2: Calculate the expression

First, calculate \( 2\times(-2)= -4 \), then \( -4 + 3 = -1 \).

For \( -4ab \) when \( a = 2 \) and \( b = -1 \):

Step1: Substitute \( a = 2 \) and \( b = -1 \)

Substitute \( a = 2 \) and \( b = -1 \) into \( -4ab \), we get \( -4\times2\times(-1) \).

Step2: Calculate the expression

First, calculate \( 2\times(-1)= -2 \), then \( -4\times(-2)= 8 \).

Answer:

For \( 2x + 3 \) when \( x = -2 \), the result is \(-1\).
For \( -4ab \) when \( a = 2 \) and \( b = -1 \), the result is \(8\).