The two lines y - ax = 2 and x + 23y = 138 are perpendicular. What is the value of a?
If you put the line equations in the form y = mx + b the slope is m
First one y -ax =2
y = ax + 2 the slope of this line is 'a'
perpindicular slope will be - 1/a
Line 2 x + 23y = 138
23y = -x + 138 divide both sides by 23
y = -1/23 x + 6 slope is -1/23
for these lines to be perpindicular: - 1/a = -1/23 so a = 23
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