You have the following expression:
2|-3x| + 1
In order to find the value of the previous expression when x = 7, consider that bars |-3x| means absolute value of -3x. The result of an absolute value is always a positive number, indeendently of the sign of the quantity inside the absolute value.
Then, when you replace x= 7, you obtain:
2|-3(7)| + 1 =
2|-21| + 1 =
2(21) + 1 =
42 + 1 =
43
Hence, the result is 43
