The points (10, -8) and (9, t) fall on a line with a slope of 0. what is the value of t?

1 Answer
Dec 16, 2016

#t=-8#

Explanation:

gradient (slope) #=("change in up or down")/("change in along")" "#

as you travel from left to right on the x-axis.

If gradient = 0 then we have:

#("change in up or down")/("change in along")" " = (y_2-y_1)/(x_2-x_1)=0/(x_2-x_1)#

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If the gradient is 0 then the line is horizontal. Thus the value of #y# is constant #(y_2=y_1)#

Given that point 1 #" "P_1->(x_1,y_1)=(10,-8)#

Then the constant value of y is -8
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However, the question uses the letter #t# instead of #y# so
#t# is a constant at #t=-8#