Question

Indicate in standard form the equation of the line passing through the given points.

B(0, 0), C(4, -4)

Answer 1

we need to find the slope using the slope formula : slope(m) = (y2 - y1) / (x2 - x1)
(0,0) x1 = 0 and y1 = 0
(4,-4) x2 = 4 and y2 = -4
now we sub
slope(m) = (-4-0) / (4 - 0)
slope(m) = -4/4 = -1

so now we have our slope(m) = -1 and we have our x and y points. We will use y = mx + b to find b.

y = mx + b
m = -1
(4,-4) x = 4 and y = -4 (you can use either set of points, I just picked this set)
now we sub
-4 = 4(-1) + b
-4 = -4 + b
0 = b

our equation is :
y = -1x + 0 (we will turn it into standard form now)
x + y = 0 ===> standard form

Answer 2

any questions ?

Answer 3

what if it wants x first?

Answer 4

Indicate the equation of the given line in standard form.

The line through (2, -1) and parallel to a line with slope of 3/4

Answer 5

a parallel line will have the same slope. So the slope we will use is 3/4.

y = mx + b
slope(m) = 3/4
(2,-1) x = 2 and y = -1
now we sub
-1 = 3/4(2) + b
-1 = 6/4 + b
-1 - 6/4 = b
-4/4 - 6/4 = b
-10/4 = b
- 5/2 = b

so our equation is :
y = 3/4x - 5/2 (multiply by the LCD, which is 4)
4y = 3x - 10 (subtract 3x from both sides)
-3x + 4y = - 10 (multiply by -1 to make x positive)
3x - 4y = 10 ===>standard form

Answer 6

what do you mean by " what if it wants x first " ?