Find the value of r so that the line through (8,r) and (4,5) has a slope of -4

r = - 11

Step-by-step explanation:

Calculate the slope m using the slope formula and equate to - 4

m =

with (x₁, y₁ ) = (4, 5) and (x₂, y₂ ) = (8, r)

m = = = - 4 ( multiply both sides by 4 )

r - 5 = - 16 ( add 5 to both sides )

r = - 11

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step-by-step explanation:

step-by-step explanation :

we know that

the measurement of the outer angle is the semi-difference of the arcs which comprises

in this problem

m< xzy is the outer angle

substitute the values

the measure of angle xoy is equal to

> by central angle

substitute the value