Find the value of this expression if x = -7 and y = -2. ху 9
1 answer:
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Answer:
see explanation
Step-by-step explanation:
If 2 lines are perpendicular then the product of their slopes equals - 1
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Consider the given equations
3x - 4y = 12 ( subtract 3x from both sides )
- 4y = - 3x + 12 ( divide terms by - 4 )
y = x - 3 ← in slope- intercept form
with slope m =
3y = 12 - 4x = - 4x + 12 ( divide terms by 3 )
y = - x + 4 ← in slope- intercept form
with slope m = -
Then
× -
= - 1
Since the product of their slopes = - 1 then the lines are perpendicular