evaluate the piece-wise function for the given values of x by matching the domain values with the range values

Can someone answer this question? : )

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76

Sundar used linear combination to solve the system of equations shown. he did so by multiplying the first equation by 5 and the second equation by another number to eliminate the y-terms. what number did sundar multiply the second equation by? 2x+9y=41 3x+5y=36