What is the missing length of side b and A?

b=42 ( base angles are equal)

a=24

then taking a as refrence angle

tan24=p/b

tan24=a/42

a= -89.66( but length cant be negative so )

a=89.66

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

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c