On which of the following lines does the point (7, 1) lie? a.) y = 5x + 4 b.) y = -x + 8 c.) y = x - 10 d.) y = -4x + 3

We have that
the point (7, 1)

case A.) y = 5x + 4
if the point (7, 1) lie to the line
so
for x=7 the value of y must be  1
y=5*7+4> y=39
39 is not 1> the point does not belong to the line

case B.) y = -x + 8
if the point (7, 1) lie to the line
so 
for x=7 the value of y must be  1
y=-7+8> y=1> the point belongs to the line

case C.) y = x - 10
if the point (7, 1) lie to the line
so 
for x=7 the value of y must be  1
y=7-10> y=-3
-3 is not 1> the point does not belong to the line

case D.) y = -4x + 3
if the point (7, 1) lie to the line
so 
for x=7 the value of y must be  1
y=-4*7+3> y=-25
-25 is not 1> the point does not belong to the line

the answer is the option
 B.) y = -x + 8