C
First you -4 from x so you have to do the opposite which is to add 4
Answer:
x = 63
Step-by-step explanation:
From the question, we can deduce the following points;
- 12 less than x which simply means 12 subtracted from x.
- the value of the above expression is equal to 51.
Translating the word problem into an algebraic expression, we have;
x - 12 = 51
Rearranging the equation (collecting like terms), we have;
x = 51 + 12
x = 63
<span>the radii of the circles is 4 / 2 = 2.</span>