Question

X-1

8
The slope of QR is *4 and the slope of ST is
3
If QR I ST, determine and state the value of x.

Answer 1

E. -1/2

Explanation:

When two lines are said to be perpendicular to each other, the slope of one is the negative reciprocal of the other.

Therefore, given that
`(x - 1)/(4)` is the slope of
`\overline{QR}`, and ⁸/3 is the slope of
`\overline{ST}`, if both lines are perpendicular, it means that the slope of
`\overline{ST}` would be the negative reciprocal of the slope of
`\overline{QR}`.

Therefore:

`(x - 1)/(4) = -(3)/(8)`

Cross multiply

`(x - 1)(8) = (-3)(4)`

`8x - 8 = -12`

Add 8 to both sides

`8x = -12 + 8`

`8x = -4`

Divide both sides by 8

`x = (-4)/(8)`

`x = (-1)/(2)`