Answer:
The student did not use the FOIL method to solve the binomials. The FOIL method is used to multiply binomials, or to multiply (x + 3) by (3x -12).
Correct Answer: (7x+3)^2= 49x^2 + 42x + 9
Explanation: Use the FOIL method: First, Outer, Inner, Last
(7x+3)(7x+3)
First: (7x)(7x) = 49x^2
Outer: (7x)(3) = 21x
Inner: (3)(7x) = 21x
Last: (3)(3) = 9
49x^2 + 21x + 21x + 9 = 49x^2 + 42x + 9