What's the equation of a line that passes through points (–1, –5) and (1, 3)?
2 answers:
Answer:
y = 4x - 1
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 =
with (x₁, y₁ ) = (- 1, - 5) and (x₂, y₂ ) = (1, 3)
m = =
= 4 , then
y = 4x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (1, 3 ) , then
3 = 4 + c ⇒ c = 3 - 4 = - 1
y = 4x - 1 ← equation of line
You might be interested in
Answer:
The actual distance between the cities is 211.67 cm.
Step-by-step explanation:
Given:
The map key indicates that 4.5 cm is equivalent to 75 cm.
Now, to find the actual distance between the cities if the cities are 12.7 cm apart on the map.
Let the actual distance be .
So, we set a proportion to find the actual distance:
4.5:12.7 = 75:x.
<em>Changing into fractions.</em>
<em>By cross multiplication we get:</em>
<em>Dividing both sides by 4.5 we get:</em>
Therefore, the actual distance between the cities is 211.67 cm.