x-intercept means the value of x at y = 0
y-intercept means the value of y at x = 0
the equation is
[tex]7x-3y=21[/tex]Substitute y by 0 to find the x-intercept
[tex]\begin{gathered} 7x-3(0)=21 \\ 7x-0=21 \\ 7x=21 \end{gathered}[/tex]Divide both sides by 7 to find x
[tex]\begin{gathered} \frac{7x}{7}=\frac{21}{7} \\ x=3 \end{gathered}[/tex]The ordered pair of x-intercept is (3, 0)
Substitute x by 0 to find the y-intercept
[tex]\begin{gathered} 7(0)-3y=21 \\ 0-3y=21 \\ -3y=21 \end{gathered}[/tex]Divide both sides by -3 to find y
[tex]\begin{gathered} -\frac{3y}{-3}=\frac{21}{-3} \\ y=-7 \end{gathered}[/tex]The ordered pair of the y-intercept is (0, -7)