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Write the equation of the line that passes through (4,-3) & (3,0)
m =
b =
y =

User Tulon
by
3.6k points

1 Answer

9 votes

Answer:

m = -3

b = 9

y = -3x + 9

Explanation:

Let us solve the question

∵ The line passes through points (4, -3) and (3, 0)

∵ The rule of the slope is m =
(y2-y1)/(x2-x1)

∵ (x1, y1) and (x2, y2) are 2 points on the line

x1 = 4 and y1 = -3

x2 = 3 and y2 = 0

→ Substitute them in the rule of the slope to find it

∵ m =
(0--3)/(3-4) =
(0+3)/(-1) = -3

m = -3

∵ The form of the equation of the line is y = m x + b

→ Substitute the value of m in the form of the equation.

y = -3x + b

→ To find b substitute x and y by the coordinates of the point (3, 0) or (4, -3)

x = 3 and y = 0

∴ 0 = -3(3) + b

∴ 0 = -9 + b

→ Add 9 to both sides

∴ 9 = b

b = 9

→ Substitute the value of b in the equation

y = -3x + 9

The equation of the line is y = 3x + 9

User Ben Quan
by
3.5k points