Help plz.

a) 3 b) y = 3x + 11

Step-by-step explanation:

a)

In order to find the gradient (slope), find the change in y or change in x (rise/run).

-2 - 2 / 7 - (-5)

-2 - 2 / 7 + 5

-4/12 = -1/3

Now that we know the gradient of line AB is -1/3, take the opposite reciprocal of that to find the gradient perpendicular to line AB.

-1/3 ⇒ 3

b)

Take point C's values and the perpendicular gradient found earlier and substitute them into the point-slope form equation.

y - 5 = 3(x - (-2))

y - 5 = 3(x + 2)

y - 5 = 3x + 6

y = 3x + 11

if a = 1,   and b = 2, then the answer is 47.99999999. if you round that to the nearest whole number, the answer is 48.