Slope-intercept from two points (4,-8) and (8,5)

Here you go :)

Slope is equal to the change in y over the change in x or rise over run:

m = change in y/change in x

The change in x is equal to the difference in x-coordinates (also called run), and the change in y is equal to the difference in y-coordinates (also called rise):

m=y2−y1/x2−x1

Substitute in the values of x and y into the equation to find the slope:

m=5−(−8)/8−(4)

Simplify:

m=13/4

Substitute the value of m into the slope-intercept form of the equation, y = m x + b :

y=(13/4)x+b

Substitute the value of x into the slope-intercept form of the equation, y = m x + b .

y = ( 13/ 4 ) ⋅ ( 4 ) + b

Substitute the value of y into the slope-intercept form of the equation, y = m x + b .

− 8 = ( 13/ 4 ) ⋅ ( 4 ) + b

Rewrite the equation as ( 13 4 ) ⋅ ( 4 ) + b = − 8 .

( 13/ 4 ) ⋅ ( 4 ) + b = − 8

Cancel the common factor.

13/ 4 ⋅ 4 + b = − 8

Rewrite the expression.

13 + b = − 8

Move all terms not containing b to the right side of the equation.

b = − 21

The values of the slope and y-intercept are m = 13 4 and b = − 21 .

m = 13 4

b = − 21

Answered by James

-6 is the correct option from the above given options

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl