Answer:
Too tired to explain, here's some digital steps by Symbolab:
H + m = 480
h = 2m
2m + m = 480
3m = 480
m = 480/3
m = 160 <=== there were 160 math books
h = 2m
h = 2(160)
h = 320 <=== there were 320 history books
Answer:
Step-by-step explanation: