No sé hacerlo ayudo necesito hacerlo ya

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.

Y= 4x + 3 y = - 1 4 x - 5 what is the best description for the lines represented by the equations?

Atruck can be rented from company a $50 a day plus $0.60 per mile. company b charges $20 a day plus $0.80 per mile to rent the same truck. find the number of miles in a day at which the rental costs for company a and company b are the same