please help me! 30 points!

Answer:
y = 9
Step-by-step explanation:
The x-coordinate of all points on the y-axis is 0. To find where the line crosses the y-axis, set x equal to zero and solve for y.
y = -4x + 9
Let x = 0:
y = -4(0) + 9
y = 0 + 9
y = 9
The line crosses the y-axis at y = 9.