Question

(7q3r2 + 5qr2 + 23q) + (−5qr2 − qr² − 11q − 4q3r2) adding polynomials horizontally

Answer 1

You can remove the  parentheses:-

= 7q^3r^2 + 5qr^2 + 23q + −5qr^2 − qr^2 − 11q − 4q^3r^2  ( because there is + outside)

Bring like terms together

= 7q^3r^2 − 4q^3r^2  + 5qr^2  − 5qr^2 − qr^2 + 23q − 11q

= 3q^3r^2 - qr^2 + 12q   answer