Solve equations with more than two unknowns.. the linear combination technique by solving the following system of two equations with two need solving this

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

John used linear combination to solve the system of equations shown. he did so by multiplying the first equation by -3 and the second equation by another number to eliminate the x-terms. what number did jonas multiply the second equation by? 4x-6y=23x+5y=11

If 5x - 2 = -12, then x = a) -50 b) -4.4 c) -2.8 d) -2