Without plotting the function y = f (x), find the coordinates of its intersection

Without plotting the function y = f (x), find the coordinates of its intersection points with the Ox and Oy axes: A) f (x) = 9x + 12 B) f (x) = – 4x + 22 B) f (x ) = 7x-28

When the function graph intersects the Ox axis (abscissa), the y coordinate is 0. When the function intersects the Oy axis (ordinate), the x coordinate is 0.
A) f (x) = 9x + 12.
Intersection with the Ox axis:
9x + 12 = 0;
9x = – 12;
x = – 12/9 (in proportion);
x = – 4/3.
Point coordinates (- 4/3; 0).
Oy-axis intersection:
y = 9 * 0 + 12;
y = 12.
Point coordinates (0; 12).
B) f (x) = – 4x + 22.
Intersection with the Ox axis:
– 4x + 22 = 0;
– 4x = – 22;
x = – 22 / (- 4) (in proportion);
x = 11/2;
x = 5.5.
Point coordinates (5,5; 0).
Oy-axis intersection:
y = (- 4) * 0 + 22;
y = 22.
Point coordinates (0; 22).
B) f (x) = 7x – 28.
Intersection with the Ox axis:
7x – 28 = 0;
7x = 28;
x = 28/7 (in proportion);
x = 4.
Point coordinates (4; 0).
Oy-axis intersection:
y = 7 * 0 – 28;
y = – 28.
Point coordinates (0; – 28).