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

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.

step-by-step explanation:

to find if any function is an inverse of the other, put the first equation in as x in the next one. then simplify and solve. if at the end you get the statement y = x, then it is an inverse. if you get anything else, it is not.