Why does deciding 10 shift each digit one place to the right?

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

Which of the following describes the graph of y--4x-36 compared to the parent square root function? stretched by a factor of 2, reflected over the x-axis, and translated 9 units right stretched by a factor of 2, reflected over the x-axis, and translated 9 units left stretched by a factor of 2, reflected over the y-axis, and translated 9 units right stretched by a factor of 2, reflected over the y-axis, and translated 9 units left save and exit next submit

How do you determine if an ordered pair is a solution to a given equation?