Answer:
Step-by-step explanation:
a) Mark any two points in line a
(0,7) ; (5,-3)
Find the slope
slope = y2 - y1 /x2-x1
Equation: y-y1 = m(x-x1)
y - 7 = -2(x - 0)
y - 7 = -2x
y = -2x + 7 --------> line a
c) equation of line b
(2,-1); slope = -2 {as b line is parallel to line a}
y - y1 =m(x-x1)
y -(-1) = -2*(x - 2)
y + 1 = -2x - 2*-2
y + 1 = -2x + 2
y = -2x + 2 -1
y = -2x +1 ------> equation of line b