Hello!
Input, is another name for the domain of a function, or an x-value. Since we are given the equation, y = 7x² + 3, we can substitute the x-value of 4, into the equation, and solve for the output, the range, or a y-value of a function.
y = 7(4)² + 3 (simplify the exponent)
y = 7(16) + 3 (use the distributive property)
y = 112 + 3 (simplify)
y = 115
Therefore, you are correct! The answer is 115. :)