To find the expression that models the remainder of Alex's workshop space after renting a portion to Matt, we need to subtract the area rented to Matt from the total area of Alex's workshop.
Given:
- Total area of workshop: \( 4x^2 + 7x - 3 \) square feet
- Area rented to Matt: \( 2x^2 + 7x + 5 \) square feet
Now, we perform the subtraction:
\[ \text{Remainder} = \text{Total area} - \text{Area rented to Matt} \]
\[ \text{Remainder} = (4x^2 + 7x - 3) - (2x^2 + 7x + 5) \]
Now, we distribute the negative sign:
\[ = 4x^2 + 7x - 3 - 2x^2 - 7x - 5 \]
Next, we combine like terms:
- For \(x^2\) terms: \(4x^2 - 2x^2 = 2x^2\)
- For \(x\) terms: \(7x - 7x = 0\)
- For constant terms: \(-3 - 5 = -8\)
Putting this all together, we have:
\[ \text{Remainder} = 2x^2 - 8 \]
So, the expression that models the remainder of Alex's workshop space once he rents out part to Matt is:
\(2x^2 - 8\) square feet.