Answer:
A
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (0, 3) and (x₂, y₂ ) = (1, 1)
m = = - 2
note the line crosses the y- axis at (0, 3) ⇒ c = 3
y = - 2x + 3 → A
Answer:
a. -⅓
b. 3
c. y = 3x - 10
Step-by-step explanation:
a. Gradient of line AB:
A(1, 3), B(7, 1)
Gradient (m) = -⅓
b. The of the line that is perpendicular to line AB would be the negative reciprocal of the gradient of line AB.
Thus, the negative reciprocal of -⅓ = 3
Gradient of the line perpendicular to line AB = 3
c. Equation of the line that passes through (4, 2) and is perpendicular to line AB:
We can write the equation using the point-slope form equation, y - b = m(x - a), where,
(a, b) represents a point on the line, and,
m = gradient/slope
We know that the gradient/slope (m) = 3
Also, a point, (a, b) = (4, 2).
Therefore, substitute a = 4, b = 2, and m = 3 into y - b = m(x - a)
Thus:
y - 2 = 3(x - 4)
y - 2 = 3x - 12
Add 2 to both sides
y = 3x - 12 + 2
y = 3x - 10
