When simplified,letter A will be your answer.
4-7x=15
The answer is 7 cm because you times 144 to 7 and you divide that answer by 7 and we get seven
Remember that an exponent means repeated multiplication.
The exponent of 4 means you have four
's mutiplied together:

And then each exponent of 2 inside means you have two
's multiplied inside each set of parentheses.:

There are 8 b's there when you expand this out.