Simplify (7y^2+3xy-9)-(2y^2+3xy-5)

$(7 y^{2} + 3 x y - 9) - (2 y^{2} + 3 x y - 5)$

Simplify each term.

Apply the distributive property.

$7 y^{2} + 3 x y - 9 - (2 y^{2}) - (3 x y) - - 5$

Simplify.

Multiply $2$ by $- 1$ .

$7 y^{2} + 3 x y - 9 - 2 y^{2} - (3 x y) - - 5$

Multiply $3$ by $- 1$ .

$7 y^{2} + 3 x y - 9 - 2 y^{2} - 3 (x y) - - 5$

Multiply $- 1$ by $- 5$ .

$7 y^{2} + 3 x y - 9 - 2 y^{2} - 3 (x y) + 5$

$7 y^{2} + 3 x y - 9 - 2 y^{2} - 3 x y + 5$

Simplify by adding terms.

Combine the opposite terms in $7 y^{2} + 3 x y - 9 - 2 y^{2} - 3 x y + 5$ .

Subtract $3 x y$ from $3 x y$ .

$7 y^{2} - 9 - 2 y^{2} + 0 + 5$

Add $7 y^{2} - 9 - 2 y^{2}$ and $0$ .

$7 y^{2} - 9 - 2 y^{2} + 5$

Subtract $2 y^{2}$ from $7 y^{2}$ .

$5 y^{2} - 9 + 5$

Add $- 9$ and $5$ .

$5 y^{2} - 4$