Distance between (-4,-5) and (4,-8)

Determine the relationship of ab and cd given the following points

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

Use sigma notation to represent the following series for 9 terms.