Question

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

Answer 1

`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`