Question

solve the system using the subsition method (if there is no solution put no solution if there is infinite put infinite

Answer 1

Given Data:

`\begin{gathered} p=-4t+28\ldots(1) \\ p=3t-21\ldots(2) \end{gathered}`

subsitute equation (1) in equation (2) we gte,

`\begin{gathered} p=3t-21 \\ p-3t=-21 \\ (-4t+28)-3t=-21 \\ -7t+28=-21 \\ -7t=-21-28 \\ -7t=-49 \\ t=(49)/(7) \\ t=7\ldots(3) \end{gathered}`

subsitute t = 7 in equation (1),

`\begin{gathered} p=-4t+28 \\ p=-4(7)+28 \\ p=-28+28 \\ p=0 \end{gathered}`

Therefore p =0 and t =7