Question

5. If x= 3 solves the system shown below, what must be the value of a?(1) -4(3) 3y = 5x - 8(2) -1(4) 7y = ax +19

Answer 1

Given data:

The given value is x=3.

Subtitute 3 for x in the expression y = 5x - 8.

`\begin{gathered} y=5(3)-8 \\ =7 \end{gathered}`

Substitute 7 for y, and 3 for x in the expression y=ax+19.

`\begin{gathered} 7=3a+19 \\ 3a=-12 \\ a=-4 \end{gathered}`

Thus, the value of a is - 4, so option (i) is correct.