the next step after writing the equation would be to subtract 10 from both sides to get 0.05x=12. after this you would then have to divide 12 by 0.05 to get 240 minutes. you could check it by putting 240 in for x to get 10+0.05(240)=22. you would then multiply 0.05 by 240 to get 12 and then add 10 onto it to get 22 which was already given.
Bob's bill is the total of the fixed fee and the charges based on minutes. The latter is 0.05m, where m is the number of minutes. Hence, Bob's July bill is ...
10 + 0.05m = 22 . . . . . total of charges for July is $22
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The equation is solved by subtracting the constant and dividing by the coefficient of m.
From the information given, the function would indicate that the weight of the dolphin after x days would be equal to the 31 pounds the baby weighed when it was born plus 2.3 lbs that is the average rate it is growing for the number of days: