(21 + 34 + x + 25 + 37 + 22) / 6 = 30
(139 + x) / 6 = 30 .....multiply both sides by 6
139 + x = 30 * 6
139 + x = 180
x = 180 - 139
x = 41......so during week 3, she rode her bike 41 miles
5x + 9y = 0
to find the x int, sub in 0 for y and solve for x
5x + 9(0) = 0
5x = 0
x = 0
to find the y int, sub in 0 for x and solve for y
5(0) + 9y = 0
9y = 0
y = 0
the reason u cannot use just the intercepts is because the line goes through the origin (0,0)....The intercepts coincide giving u only 1 point...and that is not enough to graph a line
