Question

Select all of the ordered pairs that are solutions to the equation y= -5x + 30

Answer 1

´We must substitute each pair into our equation:

A. If we substitute poin (45,3), we have

$\begin{gathered} 3=-5(45)+30 \\ 3=-195\text{ !!!!} \end{gathered}$

that is, this point doesnt belong to the line.

B. If we substitute poin (3,45), we have

$\begin{gathered} 45=-5(3)+30 \\ 45=-15+30 \\ 45=15\text{ !!!!} \end{gathered}$

then, this point doesnt belong to the line.

C. If we substitute poin (0,30), we have

$\begin{gathered} 30=-5(0)+30 \\ 30=0+30 \\ 30=30 \end{gathered}$

then, this point is a solution.

D. If we substitute poin (30,0), we have

$\begin{gathered} 0=-5(30)+30 \\ 0=-150+30 \\ 0=-120\text{ !!!} \end{gathered}$

then, this point doesnt belong to the line.

Therefore, the answer is option C