I assume you mean 3(16^7-39)?
16^7 is 268435456
268435456-39 is 268435417
268435417 multiplied by 3 is 805306251
Hope this helped.
360 meters is the answer as 9 meter in 1st second ,27 meter in 2nd and 81 in 3rd it is in a series of geometric progression ...of 9,27,81 in which 9*3 =27,27*3=81 so next number will be 81*3=243 total distance moved in 4 seconds is 243+81+27+9=360 meters
Multiplying x^2 by 5 stretches the graph vertically by a factor of 5. Try graphing both x^2 and 5x^2 and see for yourself that this is correct.