Question

What should you multiply the first equation (top equation) by in order toeliminate the variable y when the two equations are added together?(2x - 5y = 71-6x - 5y = 3

Answer 1

Given a simultaneous equation as shown below

`\begin{gathered} 2x\text{ -5y = 7} \\ -6x\text{ -5y = 3} \end{gathered}`
`\begin{gathered} \text{ multiply equation (1) by -1} \\ -2x\text{ + 5y = 7} \\ -6x\text{ -5y = 3} \end{gathered}`

Hence the variable of y in the top equation must be multiplied by -1 in order to eliminate y