Solve for the missing coordinate above
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let
A( 0,0)
B( x,23)------> missing coordinate
step 1
find the equation of the line AB
we know that
the slope of the line AB is equal to 1
because the horizontal distance is equal to the vertical distance
slope m=23/23------> m=1
with m=1 and point A (0,0)
y-y1=m*(x-x1)------> y-0=1*(x-0)-----> y=x
step 2
in the equation y=x
substitute the value of y-coordinate of point B and find the value of x
point B(x,23)
for y=23
y=x-------> 23=x
so
the x-coordinate of point B is 23
therefore
the answer is
the x coordinate is equal to 23