Slope intercept form: y=mx+b
m=slope
b= y-intercept (where the line crosses the y-axis)
You can find the slope with this following equation: (y(2)-y(1))/(x(2)-x(1))
In this case the points are (2,4) and (5,4). The first set being (2,4) and the second (5,4). This means (2,4) can be expressed as (x(1),y(1)) and (5,4) expressed as (x(2),y(2)). Plugging these numbers into the slope equation gives us: (4-4)/(5-2) = 0/3 = 0. The slope is 0 therefore the line is horizontal.
To find the y-intercept you can plug in one of the two sets of points into the point slope equation: y=mx+b , lets use (2,4) since the numbers are smaller. I get : 4= 0 (2) + b (we're looking for b the y-intercept). This gives us 4=b.
The answer is y=0x+4 or y=4.
Applying this you can solve the second one.
1) y = mx +b
m - is a slope = (y2-y1)/(x2-x1) = (4-4)/(5-2) =0
y=0*x + b
(2, 4) ----> 4=0*2 + b, b=4
y=0x+ 4, or y = 4
2)y = mx +b
m - is a slope = (12-7)/(3-(-2)) =5/5=1
y=1*x+b, y=x+b
(-2, 7) -------> y=x+b, 7= -2 +b, b =9
y=x+9
