Answer:
see explanation
Step-by-step explanation:
(a)
AC = AB + BC ← substitute values
AC = x + 2 + 7x - 3 = 8x - 1
(b)
QR = PR - PQ ← substitute values
QR = 13y + 25 - (8y + 5) ← distribute parenthesis by - 1
= 13y + 25 - 8y - 5 = 5y + 20
